Officer Nolan is forced to spend a week in solitary confinement in a quiet border town with a young local officer who is in need of some training; Sgt. Bradford and Officer Chen go under cover together in a possible drug trafficking case.

Officer John Nolan is once again face to face with serial killer Rosalind; officers Bradford and Chen work undercover with Detective Lopez and the Las Vegas Police Department to arrest leaders of a major criminal enterprise.

Officer John Nolan and the team feel they must negotiate with a distraught man who is holding a hospital hostage to ensure his wife receives a lifesaving surgery.

A search mission for three women missing in Yosemite Park turns to a murder investigation when two are discovered in the trunk of their burned out car.

Police search for the killer of an elderly upscale Toronto couple.

The largest police investigation of the decade lasted 23 days to catch a sniper who terrorized Washington, D. C. residents.

Voight's new Internal Affairs handler proves to be suspicious of his actions; Voight must work with his former partner from the Gang Unit; Halstead enlists Jin to help him gather more information on Lonnie Rodiger; Olinsky takes Ruzek down a peg.

Burgess and Atwater come across a gunshot victim and the only witness is Olinsky's daughter; Ruzek goes to Burgess for help with an undercover mission.

Halstead's badge is revoked when Lonnie Rodiger is found dead; Severide (Taylor Kinney) and Clarke (Peter Mills) find Dr. Elliot's torso; Sumner (Sydney Tamiia Poitier) tries to prove herself; Lindsay shares a moment with Severide.

Dueling gangs are suspected when a massacre occurs and $8 million is stolen; Platt asks Ruzek for help.

As Voight and his team search for the bombers, they realize there might be more bombs set to detonate; Burgess' niece fights for her life.

Cmdr. Perry notifies the unit that Pulpo has been released to help with a case; Ruzek gets difficult news; when a bit of Lindsay's past resurfaces, Voight reminds her how far she's come.

Platt and Voight discuss their pasts; Jin uses a scapegoat when he is caught tinkering with Voight's computer; Lindsay realizes she needs to come clean.

Voight's new Internal Affairs handler proves to be suspicious of his actions; Voight must work with his former partner from the Gang Unit; Halstead enlists Jin to help him gather more information on Lonnie Rodiger; Olinsky takes Ruzek down a peg.

Burgess and Atwater come across a gunshot victim and the only witness is Olinsky's daughter; Ruzek goes to Burgess for help with an undercover mission.

Halstead's badge is revoked when Lonnie Rodiger is found dead; Severide (Taylor Kinney) and Clarke (Peter Mills) find Dr. Elliot's torso; Sumner (Sydney Tamiia Poitier) tries to prove herself; Lindsay shares a moment with Severide.

Dueling gangs are suspected when a massacre occurs and $8 million is stolen; Platt asks Ruzek for help.

When a doctor vanishes after her shift, Colter uncovers a trail of stolen drugs and disguises revealing a calculated revenge plot.

Angelo learns that a previous job may be the key to unmasking The Ferryman; Dave has a big break in his investigation that could expose Angelo's true identity.

When the body of a devout Catholic divorcee is found in her smalltown Pennsylvania home, detectives must connect the dots between a silver van, a .32-caliber shell casing, and a bonanza of envelopes stuffed with cash.

Voight's new Internal Affairs handler proves to be suspicious of his actions; Voight must work with his former partner from the Gang Unit; Halstead enlists Jin to help him gather more information on Lonnie Rodiger; Olinsky takes Ruzek down a peg.

Burgess and Atwater come across a gunshot victim and the only witness is Olinsky's daughter; Ruzek goes to Burgess for help with an undercover mission.

Halstead's badge is revoked when Lonnie Rodiger is found dead; Severide (Taylor Kinney) and Clarke (Peter Mills) find Dr. Elliot's torso; Sumner (Sydney Tamiia Poitier) tries to prove herself; Lindsay shares a moment with Severide.

Dueling gangs are suspected when a massacre occurs and $8 million is stolen; Platt asks Ruzek for help.

As Voight and his team search for the bombers, they realize there might be more bombs set to detonate; Burgess' niece fights for her life.

Cmdr. Perry notifies the unit that Pulpo has been released to help with a case; Ruzek gets difficult news; when a bit of Lindsay's past resurfaces, Voight reminds her how far she's come.

Platt and Voight discuss their pasts; Jin uses a scapegoat when he is caught tinkering with Voight's computer; Lindsay realizes she needs to come clean.

When an unidentified burned corpse is found in a field, state-of-the-art forensics is turned to.

A serial rapist stalks elderly women for nearly 20 years before escalating to murder.

A sniper targeting abortion doctors turns murderous and a DNA "needle in a haystack" identifies the gunman.

Herrmann faces hazing in his new role as lieutenant; Foster suspects a young gymnast's injury is more than meets the eye; Severide is jealous of Kidd's best friend; Casey and Boden turn to P.D. after treating two victims who have similar injuries.

Casey helps a reporter uncover the truth behind a trailer park fire; Boden attempts to make peace with Grissom; Hermann, Otis and Kidd take action when Molly's receives a bad Yelp review; Severide reaches out to his father for a favor.

Gorsch continues his reign of terror at Firehouse 51, taking over Boden's morning meeting and going out on calls in Boden's place; Brett and Foster respond to a call where a Halloween prank has turned deadly serious.

Kidd and the team embark on a mission to help Severide as he struggles to process his father Benny's death; Brett suspects a teenage driver in a car accident is hiding something.

Severide lands in grave danger when Firehouse 51 battles a risky structure fire; Casey lends another helping hand to Naomi, the investigative reporter; Herrmann, Mouch, Otis and Cruz search for a tantalizing memento from Boden's past.

Firehouse 51 responds to a massive freeway accident that impacts someone close to them; Foster runs into someone from her past after a harrowing call; Casey and Naomi grow closer; Severide and Kidd's relationship is tested.

Casey and Naomi fight to escape a raging fire in Casey's apartment; Brett and the team struggle to create an engaging community fire safety presentation; Severide and Kidd's relationship reaches a crossroads.

Herrmann faces hazing in his new role as lieutenant; Foster suspects a young gymnast's injury is more than meets the eye; Severide is jealous of Kidd's best friend; Casey and Boden turn to P.D. after treating two victims who have similar injuries.

Casey helps a reporter uncover the truth behind a trailer park fire; Boden attempts to make peace with Grissom; Hermann, Otis and Kidd take action when Molly's receives a bad Yelp review; Severide reaches out to his father for a favor.

Gorsch continues his reign of terror at Firehouse 51, taking over Boden's morning meeting and going out on calls in Boden's place; Brett and Foster respond to a call where a Halloween prank has turned deadly serious.

Kidd and the team embark on a mission to help Severide as he struggles to process his father Benny's death; Brett suspects a teenage driver in a car accident is hiding something.

Severide lands in grave danger when Firehouse 51 battles a risky structure fire; Casey lends another helping hand to Naomi, the investigative reporter; Herrmann, Mouch, Otis and Cruz search for a tantalizing memento from Boden's past.

Firehouse 51 responds to a massive freeway accident that impacts someone close to them; Foster runs into someone from her past after a harrowing call; Casey and Naomi grow closer; Severide and Kidd's relationship is tested.

Casey and Naomi fight to escape a raging fire in Casey's apartment; Brett and the team struggle to create an engaging community fire safety presentation; Severide and Kidd's relationship reaches a crossroads.

Herrmann faces hazing in his new role as lieutenant; Foster suspects a young gymnast's injury is more than meets the eye; Severide is jealous of Kidd's best friend; Casey and Boden turn to P.D. after treating two victims who have similar injuries.

Casey helps a reporter uncover the truth behind a trailer park fire; Boden attempts to make peace with Grissom; Hermann, Otis and Kidd take action when Molly's receives a bad Yelp review; Severide reaches out to his father for a favor.

Gorsch continues his reign of terror at Firehouse 51, taking over Boden's morning meeting and going out on calls in Boden's place; Brett and Foster respond to a call where a Halloween prank has turned deadly serious.

Kidd and the team embark on a mission to help Severide as he struggles to process his father Benny's death; Brett suspects a teenage driver in a car accident is hiding something.

Severide lands in grave danger when Firehouse 51 battles a risky structure fire; Casey lends another helping hand to Naomi, the investigative reporter; Herrmann, Mouch, Otis and Cruz search for a tantalizing memento from Boden's past.

When an unidentified burned corpse is found in a field, state-of-the-art forensics is turned to.

A serial rapist stalks elderly women for nearly 20 years before escalating to murder.

A U.S. Army veteran goes out of his way to make his neighbors feel welcome; when a child's birthday gift goes missing, it takes only 37 days for the friendships to end in a killing spree.

A small town encounters satanic rituals and a savage killer.

Logan's widow starts a chain reaction campaign to kill people from her husband's captor's families.

A U.S. Army veteran goes out of his way to make his neighbors feel welcome; when a child's birthday gift goes missing, it takes only 37 days for the friendships to end in a killing spree.

A small town encounters satanic rituals and a savage killer.

Logan's widow starts a chain reaction campaign to kill people from her husband's captor's families.

A U.S. Army veteran goes out of his way to make his neighbors feel welcome; when a child's birthday gift goes missing, it takes only 37 days for the friendships to end in a killing spree.

Logan's widow starts a chain reaction campaign to kill people from her husband's captor's families.

A small town encounters satanic rituals and a savage killer.

Foster faces blowback after pointing out a doctor's oversight; Brett helps Casey look for a new apartment; Kidd prepares Tuesday the Dalmatian for the Fire Safety Dog Competition; a serious accusation is leveled against Severide.

Casey further investigates a motorcycle accident at the request of the victim's son; Kidd, Foster and Brett bond while helping Kidd fix a mistake; Mouch and Otis have a falling out after Otis' teasing hits a sore spot.

Cruz leads the charge in getting the firehouse to gear up for the Polar Plunge; Herrmann has a hard time bouncing back after dealing with a tough call; Foster's personal relationships begin to interfere with her job.

Brett, Foster and Kidd take a road trip to Indiana and encounter an accident involving a boys' hockey team that leaves them scrambling and relying on their instincts to save the injured; the rest of Firehouse 51 competes in the annual chili cook-off.

A spate of robberies comes to light after a firehouse lockbox key goes missing; Sgt. Hank Voight suspects a firefighter may be involved, and with Boden's support, he recruits Cruz to go undercover to help sniff out any suspicious activity.

Casey struggles after experiencing a narrow miss on a call; Otis wins a unique sporting opportunity in a raffle; Grissom turns to Severide for assistance when the mayor's office sends a task force to Firehouse 51.

As Martin races against time to divert Mony's investigation into who killed her brother, Vicki's misguided attempt to boost Tansform's profile threatens to put them right back in her crosshairs.

To repay a drug debt owed to the Italians after the Harlem riots, Bumpy Johnson robs from his own community.

When Joe Colombo carries out a gentleman's kidnapping of Mayme, Bumpy angrily prepares for a coming war.

Cruz leads the charge in getting the firehouse to gear up for the Polar Plunge; Herrmann has a hard time bouncing back after dealing with a tough call; Foster's personal relationships begin to interfere with her job.

Brett, Foster and Kidd take a road trip to Indiana and encounter an accident involving a boys' hockey team that leaves them scrambling and relying on their instincts to save the injured; the rest of Firehouse 51 competes in the annual chili cook-off.

As Martin races against time to divert Mony's investigation into who killed her brother, Vicki's misguided attempt to boost Tansform's profile threatens to put them right back in her crosshairs.

To repay a drug debt owed to the Italians after the Harlem riots, Bumpy Johnson robs from his own community.

When Joe Colombo carries out a gentleman's kidnapping of Mayme, Bumpy angrily prepares for a coming war.

A rash of break-ins shatters the peace in a tight-knit community; when residents take sides, good friends turn into deadly enemies.

Top criminal investigators, forensic scientists and behavioral analysts track three serial killers.

Hijackers commandeer a passenger jet to bargain for a prisoners release.

A rash of break-ins shatters the peace in a tight-knit community; when residents take sides, good friends turn into deadly enemies.

Top criminal investigators, forensic scientists and behavioral analysts track three serial killers.

Hijackers commandeer a passenger jet to bargain for a prisoners release.

A rash of break-ins shatters the peace in a tight-knit community; when residents take sides, good friends turn into deadly enemies.

Hijackers commandeer a passenger jet to bargain for a prisoners release.

Top criminal investigators, forensic scientists and behavioral analysts track three serial killers.

Doctors Rhodes and Downey are at odds over a patient's emergency heart surgery; Dr. Choi and a paramedic respond to a call from an injured hoarder; a woman is bitten by her own dog.

April and Dr. Halstead can't agree on how to treat a homeless alcoholic with a broken leg; Dr. Manning realizes her wedding ring has gone missing; two elderly women with the same symptoms are surprisingly linked.

Dr. Rhodes cares for Dr. Downey while Goodwin deals with personal issues; April gets hit while tending to a disorderly patient; Dr. Manning's past starts to catch up with her.

Dr. Rhodes begins his cardiothoracic surgery fellowship but gets off on the wrong foot with his new boss; Dr. Choi begins his life as chief resident; Sarah is caught off-guard by Dr. Charles; April tries to deal with her recently discovered illness.

Dr. Manning and Dr. Rhodes suspect that two separate cases involving sick babies may be connected; a homeless patient's upbeat disposition enlightens Dr. Halstead and Dr. Charles; Dr. Choi and a Navy corpsman deal with the toll of gang violence.

An Indonesian man who doesn't speak English arrives at the hospital with a mysterious illness; Dr. Halstead attends Maggie's family reunion; Dr. Rhodes accepts a complicated heart surgery without consulting Dr. Latham.

When several patients turn out to have the same rare infection, Dr. Charles' epidemiologist daughter comes in to consult; an elderly patient's son and young girlfriend disagree over his treatment; Dr. Reese tries to help a young drug addict.

Mary Jane arrives at the Gray House and is warned about Lavinia; Union officers Captain Lounsbury and Major Revere, captured at Bull Run, get mustered into the P.O.W. lockup by Confederate General Winder as Erasmus Ross looks on.

April and Dr. Halstead can't agree on how to treat a homeless alcoholic with a broken leg; Dr. Manning realizes her wedding ring has gone missing; two elderly women with the same symptoms are surprisingly linked.

Dr. Rhodes cares for Dr. Downey while Goodwin deals with personal issues; April gets hit while tending to a disorderly patient; Dr. Manning's past starts to catch up with her.

Dr. Rhodes begins his cardiothoracic surgery fellowship but gets off on the wrong foot with his new boss; Dr. Choi begins his life as chief resident; Sarah is caught off-guard by Dr. Charles; April tries to deal with her recently discovered illness.

Dr. Manning and Dr. Rhodes suspect that two separate cases involving sick babies may be connected; a homeless patient's upbeat disposition enlightens Dr. Halstead and Dr. Charles; Dr. Choi and a Navy corpsman deal with the toll of gang violence.

An Indonesian man who doesn't speak English arrives at the hospital with a mysterious illness; Dr. Halstead attends Maggie's family reunion; Dr. Rhodes accepts a complicated heart surgery without consulting Dr. Latham.

When several patients turn out to have the same rare infection, Dr. Charles' epidemiologist daughter comes in to consult; an elderly patient's son and young girlfriend disagree over his treatment; Dr. Reese tries to help a young drug addict.

Mary Jane arrives at the Gray House and is warned about Lavinia; Union officers Captain Lounsbury and Major Revere, captured at Bull Run, get mustered into the P.O.W. lockup by Confederate General Winder as Erasmus Ross looks on.

A childish joke between neighbor kids turns into an all-out war when the adults get involved; for some, the laughter will end forever.

Knowledge of insects by a forensic entomologist leads police to the killer of a wife and mother of two.

Team One must figure out how to get a Chinatown gang to release a local shop owner.

A childish joke between neighbor kids turns into an all-out war when the adults get involved; for some, the laughter will end forever.

Knowledge of insects by a forensic entomologist leads police to the killer of a wife and mother of two.

Team One must figure out how to get a Chinatown gang to release a local shop owner.

A childish joke between neighbor kids turns into an all-out war when the adults get involved; for some, the laughter will end forever.

Team One must figure out how to get a Chinatown gang to release a local shop owner.

Knowledge of insects by a forensic entomologist leads police to the killer of a wife and mother of two.

Maddie fears for herself and her co-workers when the call center is taken hostage.

Eddie's journey to rescue a boy from a well turns into a mission to save himself from his past.

The 118 fights an apartment building blaze and attempts a daring rescue of a blind woman trapped inside; Athena discovers a potentially sinister crime; Hen performs a risky medical procedure after an accident at a televised cooking show.

The 118 races to rescue a little girl in a runaway hot air balloon and help with a city power outage caused by a hijacked tree-trimmer truck; Athena's investigation into the serial rapist case puts her life in jeopardy.

The 118 rush to save lives in the aftermath of a massive train derailment.

When the Hollywood Reservoir dam breaks, Bobby and the 118 race into action to save passengers on a city bus that has crashed into a building several stories in the air; the team adjusts to life as first responders during the pandemic.

As Maggie digs into the reasons for her ex-husband Liam's return, Cal finds himself struggling with feelings of jealousy as tensions at the Crossing rise.

Port Wenn goes on lockdown when a patient with fleas sparks fears of a plague outbreak; Martin must deal with the town gossip when it revolves around him and Louisa; Aunt Sarah feels betrayed by Greg and George; Louisa has an epiphany.

Eddie's journey to rescue a boy from a well turns into a mission to save himself from his past.

The 118 fights an apartment building blaze and attempts a daring rescue of a blind woman trapped inside; Athena discovers a potentially sinister crime; Hen performs a risky medical procedure after an accident at a televised cooking show.

The 118 races to rescue a little girl in a runaway hot air balloon and help with a city power outage caused by a hijacked tree-trimmer truck; Athena's investigation into the serial rapist case puts her life in jeopardy.

The 118 rush to save lives in the aftermath of a massive train derailment.

When the Hollywood Reservoir dam breaks, Bobby and the 118 race into action to save passengers on a city bus that has crashed into a building several stories in the air; the team adjusts to life as first responders during the pandemic.

As Maggie digs into the reasons for her ex-husband Liam's return, Cal finds himself struggling with feelings of jealousy as tensions at the Crossing rise.

Port Wenn goes on lockdown when a patient with fleas sparks fears of a plague outbreak; Martin must deal with the town gossip when it revolves around him and Louisa; Aunt Sarah feels betrayed by Greg and George; Louisa has an epiphany.

Differences over how to enjoy life in a rural neighborhood quickly escalate into a feud that comes to a bloody end on the road where it began.

A serial killer in Spokane, Wash. murders prostitutes and leaves a bag with a smiley face on the victim's head.

A violent patient takes a guard hostage and injures a fellow patient.

Differences over how to enjoy life in a rural neighborhood quickly escalate into a feud that comes to a bloody end on the road where it began.

A serial killer in Spokane, Wash. murders prostitutes and leaves a bag with a smiley face on the victim's head.

A violent patient takes a guard hostage and injures a fellow patient.

Differences over how to enjoy life in a rural neighborhood quickly escalate into a feud that comes to a bloody end on the road where it began.

A violent patient takes a guard hostage and injures a fellow patient.

A serial killer in Spokane, Wash. murders prostitutes and leaves a bag with a smiley face on the victim's head.

A car crash at the Chicago Marathon leaves victims in critical condition; April and her medical resident brother must perform an intense operation in the field; an 8-year-old girl experiences sudden hearing loss; Dr. Choi treats a malnourished woman.

A young cancer patient struggles to tell her parents about her condition; Dr. Reese turns to Dr. Charles and Detective Lindsay for help with a troubled young man; a teen science geek and her friends impress Dr. Choi and Natalie.

Goodwin reunites with her childhood sweetheart; Dr. Halstead gets lured into a concierge doctor app idea; Dr. Rhodes treats a woman with a heart infection against the advice of Dr. Charles; a former patient of Reese's reaches out for help.

Halstead and Manning deal with two feuding brothers, one of which is in dire need of a kidney; a patient of Dr. Reese's comes to a crossroad; a 16-year-old with a genetic condition needs surgery, but the overprotective mother gets in the way.

Dr. Charles is tasked with evaluating a patient as a possible heart recipient; Jeff makes a confession to Dr. Manning; two MMA fighters arrive at Chicago Med in bad shape; Dr. Stohl returns from his sabbatical.

A heart transplant patient gets into a car accident, revealing issues that could complicate her surgery; the police officer who arrested Maggie is brought to Chicago Med with a serious injury.

On a busy night, Dr. Reese deals with having to pronounce several patients dead; April is pressured to slow down; Dr. Charles has important news for Dr. Latham; Goodwin asks Dr. Rhodes to help an unusual patient.

A tightknit community is left shattered when its school superintendent is gunned down at his upstate New York home; law enforcement's big break comes when a panic-stricken caller claims to know who the killer is.

A young cancer patient struggles to tell her parents about her condition; Dr. Reese turns to Dr. Charles and Detective Lindsay for help with a troubled young man; a teen science geek and her friends impress Dr. Choi and Natalie.

Goodwin reunites with her childhood sweetheart; Dr. Halstead gets lured into a concierge doctor app idea; Dr. Rhodes treats a woman with a heart infection against the advice of Dr. Charles; a former patient of Reese's reaches out for help.

Halstead and Manning deal with two feuding brothers, one of which is in dire need of a kidney; a patient of Dr. Reese's comes to a crossroad; a 16-year-old with a genetic condition needs surgery, but the overprotective mother gets in the way.

Dr. Charles is tasked with evaluating a patient as a possible heart recipient; Jeff makes a confession to Dr. Manning; two MMA fighters arrive at Chicago Med in bad shape; Dr. Stohl returns from his sabbatical.

A heart transplant patient gets into a car accident, revealing issues that could complicate her surgery; the police officer who arrested Maggie is brought to Chicago Med with a serious injury.

On a busy night, Dr. Reese deals with having to pronounce several patients dead; April is pressured to slow down; Dr. Charles has important news for Dr. Latham; Goodwin asks Dr. Rhodes to help an unusual patient.

A tightknit community is left shattered when its school superintendent is gunned down at his upstate New York home; law enforcement's big break comes when a panic-stricken caller claims to know who the killer is.

New neighbors disrupt the harmony that has existed between residents for years; alliances change and terror reigns until a winter storm puts a bloody end to the feud.

Officials look to state-of-the-art DNA analysis to help capture a serial killer in the Louisiana State University area of Baton Rouge.

A bold heist at a stadium lures Team One into an ex-cop's violent plan to defeat the man he blames for ruining his life.

New neighbors disrupt the harmony that has existed between residents for years; alliances change and terror reigns until a winter storm puts a bloody end to the feud.

Officials look to state-of-the-art DNA analysis to help capture a serial killer in the Louisiana State University area of Baton Rouge.

A bold heist at a stadium lures Team One into an ex-cop's violent plan to defeat the man he blames for ruining his life.

New neighbors disrupt the harmony that has existed between residents for years; alliances change and terror reigns until a winter storm puts a bloody end to the feud.

A bold heist at a stadium lures Team One into an ex-cop's violent plan to defeat the man he blames for ruining his life.

Officials look to state-of-the-art DNA analysis to help capture a serial killer in the Louisiana State University area of Baton Rouge.

Officer John Nolan moves closer to his new role as a training officer; John must uncover the truth about another officer's suicide; Lucy's successful undercover assignment earns her an invitation for specialized training.

Officer John Nolan is assigned his first rookie, Officer Celina Juarez, whose unconventional approach to police work poses a unique challenge for him.

Rosalind returns with a vengeance and Bailey's life is left hanging in the balance; Nolan is forced to make a deadly decision after a harrowing ultimatum.

Nolan and Juarez are on the hunt for a fugitive after a car incident goes awry; a past injury comes to haunt Tim and Lucy comes through during his time in need in more ways than one.

Nolan and Celina investigate a cash deposit linked to an old DEA case; Wesley grows increasingly concerned about his deposition and is shocked when he realizes Elijah's attorney is a familiar face from his past.

Officer John Nolan and Celina witness a shooting and realize the victim is already dead; Bailey has been feeling off-center since the proposal, leaving Nolan to wonder what he can do to make her feel better.

After a veteran stuntman disappears following a risky stunt, his girlfriend calls Colter to investigate.

Major revelations threaten to upend Angelo's family; Joe gets the opportunity of a lifetime.

Officer John Nolan is assigned his first rookie, Officer Celina Juarez, whose unconventional approach to police work poses a unique challenge for him.

After a veteran stuntman disappears following a risky stunt, his girlfriend calls Colter to investigate.

Major revelations threaten to upend Angelo's family; Joe gets the opportunity of a lifetime.

Nolan and Celina investigate a cash deposit linked to an old DEA case; Wesley grows increasingly concerned about his deposition and is shocked when he realizes Elijah's attorney is a familiar face from his past.

Officer John Nolan and Celina witness a shooting and realize the victim is already dead; Bailey has been feeling off-center since the proposal, leaving Nolan to wonder what he can do to make her feel better.

Officers John Nolan and Celina Juarez are in a race against time to stop the source of an explosive rampage.

Officer John Nolan moves closer to his new role as a training officer; John must uncover the truth about another officer's suicide; Lucy's successful undercover assignment earns her an invitation for specialized training.

Investigating a series of fires in California's Sam Joaquin Valley that killed four, investigators determine a respected arson investigator may be the arsonist.

Investigators work to solve a double homicide in the small town of Hudson, Wisc.

Police must use forensic science to solve the mystery of a prominent businessman whose burnt body is discovered.

Atwater settles into his new role; Lindsay turns to Voight for help; Jin is confronted about his meetings with Stillwell.

As the Sheldon Jin investigation moves forward, Internal Affairs keeps a close eye on Voight; Voight's vehicle is T-boned while following an armored car carrying Ruzek; Burgess meets her new partner; Lindsay visits her mom.

Several murder victims are found with a dollar bill pinned to their chests; Voight makes a discovery about a friend; a series of home invasions.

When a bartender takes a bullet intended for Halstead, the bounty on him becomes more real; following a tense interaction, Platt and Nadia reach an understanding.

The team races against the clock when two teenage girls disappear; Voight seeks honest answers from the father of one of the girls.

Voight is attacked and abducted while trying to help Olive; Roman and Burgess search for a girl who has taken off with a police badge.

Ruzek and Atwater go under cover as prison inmates in order to find the man they believe killed a 10-year-old girl; Burgess and Roman give a tour of the district to some boys they believe are part of the Police Explorers program.

Atwater settles into his new role; Lindsay turns to Voight for help; Jin is confronted about his meetings with Stillwell.

As the Sheldon Jin investigation moves forward, Internal Affairs keeps a close eye on Voight; Voight's vehicle is T-boned while following an armored car carrying Ruzek; Burgess meets her new partner; Lindsay visits her mom.

Several murder victims are found with a dollar bill pinned to their chests; Voight makes a discovery about a friend; a series of home invasions.

Port Wenn goes on lockdown when a patient with fleas sparks fears of a plague outbreak; Martin must deal with the town gossip when it revolves around him and Louisa; Aunt Sarah feels betrayed by Greg and George; Louisa has an epiphany.

After a veteran stuntman disappears following a risky stunt, his girlfriend calls Colter to investigate.

Major revelations threaten to upend Angelo's family; Joe gets the opportunity of a lifetime.

A tightknit community is left shattered when its school superintendent is gunned down at his upstate New York home; law enforcement's big break comes when a panic-stricken caller claims to know who the killer is.

Port Wenn goes on lockdown when a patient with fleas sparks fears of a plague outbreak; Martin must deal with the town gossip when it revolves around him and Louisa; Aunt Sarah feels betrayed by Greg and George; Louisa has an epiphany.

As the Sheldon Jin investigation moves forward, Internal Affairs keeps a close eye on Voight; Voight's vehicle is T-boned while following an armored car carrying Ruzek; Burgess meets her new partner; Lindsay visits her mom.

Several murder victims are found with a dollar bill pinned to their chests; Voight makes a discovery about a friend; a series of home invasions.

When a bartender takes a bullet intended for Halstead, the bounty on him becomes more real; following a tense interaction, Platt and Nadia reach an understanding.

The team races against the clock when two teenage girls disappear; Voight seeks honest answers from the father of one of the girls.

Voight is attacked and abducted while trying to help Olive; Roman and Burgess search for a girl who has taken off with a police badge.

Ruzek and Atwater go under cover as prison inmates in order to find the man they believe killed a 10-year-old girl; Burgess and Roman give a tour of the district to some boys they believe are part of the Police Explorers program.

A phantom white supremacist sect takes credits for bombings and bank robberies in Spokane, Wash., but FBI forensic photo analysts clears the picture.

When the prime subject for four factory deaths has a perfect alibi, investigators use video analysis, timeline reconstruction and a 3-year old fingerprint to solve the crime.

Sixteen years after a college student is found raped and strangled on a buffalo bike path, DNA technology and other clues help catch the killer.

Severide gets angry at Cruz when he feels his orders were disobeyed in the field; Boden reconnects with an old high school friend during a call to a house fire. Herrmann has issues when one of his favorite knick-knacks from Molly's goes missing.

A horrible storm wreaks havoc on Chicago and impacts Firehouse 51 when the power goes off; when a little boy mysteriously shows up at the station, everyone works together to uncover who he belongs to; Foster and Kidd argue about Severide.

Severide and Boden search to uncover whether arson was the cause of a fire at a hair salon; Mouch, Herrmann, Otis and Kidd make a startling discovery while tracking down the missing piercing nozzle from Engine 27.

A serial arsonist cold case is reopened when Lt. Severide finds a connection to a recent salon fire; Firehouse 51 celebrates a retirement party.

Severide and Kidd continue to investigate Benny's old arson case; unexpected news leads Brett to ponder a big decision; all hell breaks loose.

The mattress factory fire spirals out of control; truck and squad lay it on the line in hopes of getting the trapped victims out alive.

Casey struggles to get Boden to sign off on an energetic new recruit; Foster extends an olive branch to her irritating new medic; Otis inspires Herrmann to seek new partners at Molly's; Brett realizes life in Fowlerton will take some getting used to.

Severide gets angry at Cruz when he feels his orders were disobeyed in the field; Boden reconnects with an old high school friend during a call to a house fire. Herrmann has issues when one of his favorite knick-knacks from Molly's goes missing.

A horrible storm wreaks havoc on Chicago and impacts Firehouse 51 when the power goes off; when a little boy mysteriously shows up at the station, everyone works together to uncover who he belongs to; Foster and Kidd argue about Severide.

Severide and Boden search to uncover whether arson was the cause of a fire at a hair salon; Mouch, Herrmann, Otis and Kidd make a startling discovery while tracking down the missing piercing nozzle from Engine 27.

A serial arsonist cold case is reopened when Lt. Severide finds a connection to a recent salon fire; Firehouse 51 celebrates a retirement party.

Severide and Kidd continue to investigate Benny's old arson case; unexpected news leads Brett to ponder a big decision; all hell breaks loose.

The mattress factory fire spirals out of control; truck and squad lay it on the line in hopes of getting the trapped victims out alive.

Casey struggles to get Boden to sign off on an energetic new recruit; Foster extends an olive branch to her irritating new medic; Otis inspires Herrmann to seek new partners at Molly's; Brett realizes life in Fowlerton will take some getting used to.

Severide gets angry at Cruz when he feels his orders were disobeyed in the field; Boden reconnects with an old high school friend during a call to a house fire. Herrmann has issues when one of his favorite knick-knacks from Molly's goes missing.

A horrible storm wreaks havoc on Chicago and impacts Firehouse 51 when the power goes off; when a little boy mysteriously shows up at the station, everyone works together to uncover who he belongs to; Foster and Kidd argue about Severide.

Severide and Boden search to uncover whether arson was the cause of a fire at a hair salon; Mouch, Herrmann, Otis and Kidd make a startling discovery while tracking down the missing piercing nozzle from Engine 27.

A serial arsonist cold case is reopened when Lt. Severide finds a connection to a recent salon fire; Firehouse 51 celebrates a retirement party.

Severide and Kidd continue to investigate Benny's old arson case; unexpected news leads Brett to ponder a big decision; all hell breaks loose.

A phantom white supremacist sect takes credits for bombings and bank robberies in Spokane, Wash., but FBI forensic photo analysts clears the picture.

When the prime subject for four factory deaths has a perfect alibi, investigators use video analysis, timeline reconstruction and a 3-year old fingerprint to solve the crime.

Neighbors take sides after someone decides to build a dream home on their quiet street; longtime friends turn into hardcore enemies and death is right around the corner.

A Texas playboy is murdered and police uncover x-rated photos, shocking videos and an object hidden inside the victim's body.

Spike finds himself held at gunpoint; the team races to a shots-fired call.

Neighbors take sides after someone decides to build a dream home on their quiet street; longtime friends turn into hardcore enemies and death is right around the corner.

A Texas playboy is murdered and police uncover x-rated photos, shocking videos and an object hidden inside the victim's body.

Spike finds himself held at gunpoint; the team races to a shots-fired call.

Neighbors take sides after someone decides to build a dream home on their quiet street; longtime friends turn into hardcore enemies and death is right around the corner.

Spike finds himself held at gunpoint; the team races to a shots-fired call.

A Texas playboy is murdered and police uncover x-rated photos, shocking videos and an object hidden inside the victim's body.

Brett and Foster question the suspicious circumstances surrounding an attack at a juvenile detention center; a convoluted new technology at Firehouse 51 tests everybody's patience; Kidd is chosen to represent the district at a leadership conference.

A rare but deadly bacteria takes its toll on numerous victims around the city, leaving Chicago's finest first responders to work together alongside the CDC to resolve the dangerous situation; Severide suspects something bigger is happening.

Kidd must prove herself at the National Firefighter Leadership Conference, while the rest of Firehouse 51 is called to two eerily similar car wrecks; Mouch tries to keep the firehouse informed by starting a newsletter; Cruz deals with a heartbreak.

Cruz and Severide suspect foul play when a fire started by an elderly woman turns deadly. Kidd, Foster and Brett create a women's-only lounge. Firehouse 51 celebrates some good news.

Severide must make a tough decision about the future of his career at Firehouse 51; Herrmann deals with the consequences of his temper; Cruz is excited to demonstrate the Slamigan at the Firefighting Expo; Commissioner Grissom returns.