At Halloween, the team takes on a case to prove the existence of ghosts on the Queen Mary but find a ship on a deadly collision course; Walter considers taking note of Paige's interests to benefit their relationship.

A device that can prevent a nuclear meltdown is tracked through the Los Angeles sewers; Walter learns to listen and not offer advice to Paige; the team meets their new neighbor.

Team Scorpion visits a renaissance festival, but the revelry is cut short when a group tries to rob a nearby police evidence locker; Paige grows weary of Walter pointing out the historical inaccuracies at the festival.

Team Scorpion becomes stranded on a floating island of trash they were trying to destroy; Toby works with Cabe to uncover the details of his father's death.

The BAU is called to investigate when two members of a conspiracy group in Roswell, N.M., perish in quick succession.

When a series of backyard pool homicides are reported in California, the BAU team searches for an UnSub which has a puzzling past.

The BAU team's investigation into the home invasion and attempted homicide of a police chief's wife uncovers a world of secrets in a small town in Virginia.

The BAU is called to New York when several casualties of a brutal nature are reported in Central Park.

The BAU is called to investigate a series of homicides in which cryptic messages are found inside the mouths of the victims.

The BAU is called when the New Orleans Police Department discovers a mass grave inside a vandalized above-ground crypt in a local cemetery.

The FBI's assistant director of national security joins the BAU as it investigates the quadruple homicide of a group of roommates in St. Louis.

The BAU meets in secret to investigate a subject who appears to be kidnapping and photographing young women.

The team investigates the murder of a Navy captain who was searching for a priceless 200-year-old fleur-de-lis during the annual Louisiana Pirate Festival.

Pride, Sebastian and Tammy travel to South America after Pride is personally requested by a former colleague to assist with a classified operation that has been compromised.

Percy and Lasalle go under cover at a high-stakes poker game after the organizer targets players with access to a naval research laboratory; Laurel Pride visits her dad during spring break to discuss options after her upcoming graduation.

Pride and his bar patrons are held hostage by a group of volatile thieves.

When a board member of a soon-to-be-public medical tech company is murdered, the team tries to find out who had the most to gain from his death; OA is conflicted when pressure to help a family member is at odds with his commitment to tell the truth.

A car crash results in the death of a photographer; Maggie sympathizes with his widow when she notices similarities with her own husband's death.

After an altercation with a student, teacher Patrick Miller goes missing, leading the team to investigate everyone who might have had a grudge against him; a key witness in the case steps up to help.

A former kidnapping victim is linked to a series of murders that includes the daughter of an NYPD detective; Kristen begins to doubt her ability as an agent after a training exercise leaves her shaken.

After a businessman with a history of harassment claims against him is killed, the team suspects the killer may be one of his many accusers.

A bank holdup leads the team to a safe deposit box, the contents of which have the potential to destroy national security; Kristen is eager to get back into field work while other team members still have their concerns.

Team Scorpion tries to help a father and his daughter when their plane crashes nearby; Paige helps Walter navigate his feelings about Cabe's possible future in prison.

The team anxiously awaits the verdict of Cabe's trial which could send him to prison; they use their nervous energy to try saving a dog stuck in a cistern.

On Christmas Eve, Walter becomes unconscious after falling down the stairs and enters a dream world where Team Scorpion never existed.

The team must work with Toby's nemesis and his wife -- Toby's ex-fiancée -- when they are locked inside an artificially intelligent doomsday bunker that aims to kill them; Walter is distracted by a dream in which he married Florence instead of Paige.

Power is knocked out in Los Angeles, and the team must help a teen pilot and his girlfriend who are lost over the Pacific without any radio contact; Walter must look after a group of Ralph's classmates; Cabe tries to tell Allie that he loves her.

Team Scorpion must prevent an incoming tsunami from hitting a vulnerable nuclear power facility; Toby secretly helps his ex-fiancee retrieve her stolen identity.

The BAU is called to Oklahoma to investigate a murderous clown who is terrorizing a town.

The BAU travels to Chicago to investigate a case where red roses are left on victims; Rossi gets an unexpected visit from his ex-wife.

The BAU takes charge of a hostage situation at a law firm where Matt Simmons' wife works.

The BAU is called upon when bioterrorism is suspected in a series of mysterious deaths; Garcia visits her stepbrother to take care of a difficult family issue.

The BAU is called to Taos, N.M., when someone targets victims' temporal lobes.

The team questions the credibility of a former FBI agent's bizarre account.

When Reid and Garcia are abducted by a mass murderer, it's up to the rest of the team to find them; the BAU looks to their past to solve why the two heroes have been targeted.

The team tracks a serial killer when remains of numerous victims are found in the walls of an elderly couple's home; the hunt becomes urgent after the BAU learns the killer's specific ritual of when to strike; Rossi reconnects with his ex-wife.

Gregorio calls on her former behavioral science professor when the team's latest case matches one she studied during FBI training.

A journalist posts a scathing article documenting Pride's "reckless use of justice"; the team is concerned about the fallout from the piece and the confidential information revealed; Rita Devereaux tells Pride it is a coordinated attack on him.

Pride assembles an off-the-books team to search for a loophole when he faces a grand jury indictment for abuse of power.

Pride's teams uncover a sinister plot during the New Orleans Tricentennial Fleet Week celebration.

The son of a retired FBI agent is kidnapped, and the team must investigate if it's an act of revenge; Isobel must make a hard call when information from the past comes to light.

When an attorney is found dead near the body of a private escort, the team must piece together what connected the two seemingly random victims; Jubal's connection with one of the victims makes finding the killer much more personal.

After a truck filled with armor-piercing rifles is hijacked, the team works to discover who stole it, and what they have planned for the stolen weapons; a friend from OA's past returns to help with the case, but OA isn't sure he can trust him.

After the police ignore a desperate father's plea for help, he abducts a billionaire's daughter and holds her hostage in a safe room until his own missing child is returned to him; Jubal puts his hostage negotiation skills to the test.

When the team is called to the scene of a murder, it quickly suspects political motivation; Maggie contemplates a decision that could affect her entire career.

Jess LaCroix and his team come to help OA find a fugitive LaCroix arrested years ago after a bus with 26 students goes missing and he's the main suspect.

The murder of a jeweler leads detectives to an illegal prostitution ring; Jack McCoy's job is threatened.

The beating death of a stockbroker causes a battle of epic proportions between the victim's family and the faction responsible for his death.

A mentally challenged man is reunited with his mother, who gave him away after his brother was killed.

A young woman (guest star Jena Malone) escapes from a polygamous cult.

A crane collapse kills a man, and it may not have been an accident; a rift forms between Jack McCoy and Michael Cutter.

A revered sheriff becomes a possible conspirator in a case involving a murdered tourist.

Detectives Lupo and Bernard investigate when the writer of a best-selling memoir is found dead in a community of male prostitutes.

Cutter is determined to expose misconduct when he realizes an old friend working in the system is obstructing justice in the murder of an environmentalist.

While investigating the murder of two divorce lawyers, detectives Lupo and Bernard uncover a child slave-trade ring.

The murder of the plaintiff in a high-profile lawsuit against a major airline leads detectives to a defense attorney (Dallas Roberts) who is willing to do whatever it takes to ensure his big payday.

When the son and housekeeper of a pair of prominent biologists are murdered, detectives suspect the couple's work on a controversial pharmaceutical study may have made them targets for the killer.

The owner of a trucking company, Vic Russell, is found dead after a business meeting; detectives uncover information that leads them to believe that Russell had ties to the Russian mob.

An NYPD officer kills a troubled fellow officer who took hostages at gunpoint; detectives Lupo and Bernard find valuable stolen documents and a dead body at the man's apartment.

An unconscious war widow and her lifeless infant are found in the rubble of a bombed Army recruitment center; DA Jack McCoy must make one of the most-unpopular decisions of his career.

While Pride fights for his life in the ICU, the team scours the city for the hit woman who attempted to assassinate him.

The team searches for a former Irish Republican Army bomb maker who was smuggled into the city; they are joined by agent Hannah Khoury, Pride's replacement during his medical leave; Pride considers a new position within the agency.

The team investigates the murder of a Navy intelligence officer killed during a conference for foreign diplomats; Pride has some trouble adjusting to his new position at the agency.

An investigation into the murder of a petty officer reveals a conspiracy in a tight-knit local fishing community; Lasalle awaits the final results of the tax fraud investigation into his family's company.

With their lives in danger, Gibbs and Ziva's rogue investigation takes an unexpected turn when a possible terrorist plot is revealed.

After the body of a Marine lieutenant is found hidden under an 18-wheeler, the team tracks the vehicle's previous locations to pinpoint the crime scene and suspect; Sloane encourages the team to sit down and talk about Ziva's recent reappearance.

The team links a bizarre crime scene at Arlington National Cemetery to a string of attacks on homeless veterans; Vance orders McGee, Bishop and Torres to complete hours of evidence garage cleanup for withholding information.

NCIS investigates Marine Cpl. Laney Alimonte after evidence suggests she murdered her neighbor while being treated for insomnia by a hypnotherapist; Gibbs befriends his new neighbors after the 9-year-old's baseball crashes through his window.

After a petty officer's son is found murdered, evidence suggests Kasie's lifelong best friend is guilty.

While investigating a Marine's murder, the NCIS team uncovers a labyrinth of live-streaming spy cameras hidden in the rooms of a Virginia motel.

The NCIS team investigates the murder of a musician in the Navy's most elite band.

The NCIS team investigates a petty officer's murder that was livestreamed on a popular gaming app; Gibbs watches his 11-year-old neighbor when his mom must leave on a last-minute trip.

Gibbs and the team assist Ziva with "the one thing" she said she would need to take care of before returning to see her family.

Gibbs must face the reality of his actions after he assists Ziva with "the one thing" she said she would need to take care of before returning to her family.

John Gustafson (Jack Lemmon) and Max Goldman (Walter Matthau) are two curmudgeonly neighbors who have been at each other's throats for years. The rivalry of the former friends intensifies when Ariel (Ann-Margret) comes along and provides a love interest for both of them. When Max finds out that John is experiencing family troubles and financial ruin, however, he steps in to help. Their bond is further cemented when John has a health scare and Max makes the ultimate sacrifice for his friend.

Elderly, angling and contentious friends Max (Walter Matthau) and John (Jack Lemmon) back-burner their bickering when their kids (Kevin Pollak, Daryl Hannah) get engaged, but fishing season opens a can of romantic worms as newcomer Maria (Sophia Loren) plans to turn their beloved bait shop into a restaurant. Botched matchmaking leads to some major romantic mix-ups, until an unexpected death in the family helps everyone realize that the most important thing in life is love.

John Gustafson (Jack Lemmon) and Max Goldman (Walter Matthau) are two curmudgeonly neighbors who have been at each other's throats for years. The rivalry of the former friends intensifies when Ariel (Ann-Margret) comes along and provides a love interest for both of them. When Max finds out that John is experiencing family troubles and financial ruin, however, he steps in to help. Their bond is further cemented when John has a health scare and Max makes the ultimate sacrifice for his friend.

Elderly, angling and contentious friends Max (Walter Matthau) and John (Jack Lemmon) back-burner their bickering when their kids (Kevin Pollak, Daryl Hannah) get engaged, but fishing season opens a can of romantic worms as newcomer Maria (Sophia Loren) plans to turn their beloved bait shop into a restaurant. Botched matchmaking leads to some major romantic mix-ups, until an unexpected death in the family helps everyone realize that the most important thing in life is love.

Pride's father, Cassius Pride, is wrapped up in an NCIS case involving a notorious unsolved casino heist; Pride meets a family member he never knew existed.

After Pride's assistant escapes from a kidnapper, the team uncovers evidence of a suspect who is harvesting organs from multiple victims; Pride turns to a friend for guidance as he struggles with the ramifications of his recent brush with death.

Following a deadly car explosion in the French Quarter, the team interrogates a professor and former member of a student protest organization; Tammy discovers a secret about Hannah's personal life.

The team places Mateo Diaz, a high school gang member turned informant, in protective custody while they investigate the murder of his junior reserve officers' training corps instructor; Pride needs his brother's help to gain Mateo's trust.

The team investigates the murder of a Navy contractor who secretly lived two lives for decades.

Pride is given a series of tasks to complete by unknown assailants who are holding Wade and his father hostage.

Pride and the team hope to take down a secret and lethal group of former intelligence agents and avenge the death of someone close to them.

The NCIS team investigates an F-18 crash and the subsequent disappearance of the pilot; McGee reluctantly discusses a very personal decision with his teammates.

After a body is found at an unmanned aerial vehicle testing site, the NCIS team must determine if the death was murder or an accident; Palmer carefully interviews medical examiner assistant candidates.

After Torres and Bishop are victims of a hit-and-run, Torres fights for his life in the Intensive Care Unit.

The lead suspect in a murder investigation is a woman that Gibbs' friend met on a dating site; Sloane has a secret admirer on Valentine's Day.

The team tries to piece together how a retired Navy officer obtained a rare and valuable coin.

A Navy officer is murdered the same way his parents were murdered a decade ago; the team stumbles across a storage container filled with dollhouses that display re-creations of murder scenes; the team members agree to clean out their living spaces.

The body of a well-regarded Navy technician is found floating in a lake, which isn't far from where a popular community event takes place; Sloane's daughter makes an unexpected request.

When Kasie and Jimmy are held hostage in a diner after a jewelry store robbery goes awry, they attempt to keep the other customers safe from the thieves.

The team tries to verify the identity of Joe Smith, who claims he served on the U.S.S. Arizona during the attack on Pearl Harbor and wants to be buried there upon his death.

Gibbs and Fornell attempt to track down the leader of a drug ring who supplied drugs to Fornell's daughter; the team deals with the case of a missing cadaver from the NCIS autopsy room.

Flashbacks reveal the murder case that first introduced young Gibbs to NCIS and to Ducky.

The discovery of two dead bodies in a forest leads the NCIS team into the wild world of modern-day treasure hunting; Gibbs and Fornell get deeper into their search for the opioid kingpin.

Packages with gruesome contents are delivered to six people in the Washington, D.C.. area; Simmons and Kristy struggle to connect with their son, David, who is suspended from school for aggressive behavior.

Soon after the BAU steps in to help local law enforcement isolate a suspect for a murder, a second person who is related to the first victim is killed under similar circumstances; Prentiss is concerned about Garcia's behavior.

The BAU investigates a spooky local ghost story of the "Tall Man" and the clues it provides when two people go missing in the woods; a third person mysteriously surfaces the following day with limited details as to what happened to her friends.

The BAU investigates four murders along the eastern seaboard; the crimes become personal for Alvez when the team discovers there are ties to his time spent in pursuit of a notorious hit man; Alvez and his girlfriend decide to move in together.

The BAU races to capture the vigilantes behind a series of attacks taking place every 27 minutes in the nation's capital; Prentiss and Unit Chief Andrew Mendoza lead the effort to identify the vigilantes and what's motivating them.

The BAU investigates a double homicide and kidnapping in New Hampshire; Rossi's plans to elevate his relationship with Krystall don't go as planned.

A professor from Lewis' past tips off the BAU to an alarming number of overdose deaths of patients who just completed rehab.

Prentiss faces her past when the BAU is sent to investigate the murders of prominent businessmen, all of whom are missing their hearts; Prentiss plans a romantic first date with Mendoza, but the evening is cut short by an urgent call from Rossi.

While under cover, Gregorio joins a social club for military wives after one of the members is contacted by an ex-boyfriend who is on the FBI's most wanted list.

NCIS investigates the disappearance of a Navy entomologist after a deadly shooting at a research lab; the team finds that a rare and deadly virus was stolen.

Pride and the team reunite with conspiracy journalist Oliver Crane after the source for his latest story is murdered; Hannah's former partner, Liam Somers, surprises her and shares a shocking revelation about an old case.

The team investigates multiple murders tied to a construction company that creates an experimental chemical that strengthens sea walls; evidence from Hannah's previous mission in Oman is used against her.

After an elusive terrorist with a personal vendetta against Hannah resurfaces, she and her family are placed in protective custody while the team searches for the suspect.

After a reshuffling of assignments, Pride returns to the New Orleans office during the investigation of a missing petty officer.

The NCIS team investigates the murder of Patton's friend, a former Navy SEAL gunned down in a drive-by shooting while Patton watched.

Mysterious e-mails from a religious Web site lead detectives to the dead body of one of the page's creators; Jack McCoy's political opponent uses the media to attack his reputation.

As detectives investigate the death of a bank executive's mistress, they uncover a kidnapping and extortion plot.

The search for a writer's killer leads detectives to a closed espionage case.

While investigating the murder of a TV reporter, detectives learn that she was involved in a love triangle.

Detective Bernard and Lupo's investigation into a series of hate crimes against Hispanic men leads to controversy.

Detectives Lupo and Bernard have trouble finding a motive when a firefighter and his wife are found tortured and murdered in their new home.

The double murder of two young scientists leads detectives to a jealous, mentally disturbed woman.

Detectives Lupo and Bernard investigate three murders that appear to be the work of a serial killer.

The murder of a well-known charity executive leads detectives down a path of political intrigue.

When a young war veteran is found dead, Detectives Lupo and Bernard connect the murder to an attorney who used to work for the Department of Justice.

Detectives find that DNA evidence seems to link the murder of a CSU investigator and an attack on a young journalist (Camille Chen).

Detectives Lupo and Bernard investigate when an aspiring musician is found dead; a bag of cash leads to multiple suspects.

While searching for the murderer of the adoptive mother of 10 disabled children, detectives uncover a reality-show offer and an affair.

When a doctor is murdered, the detectives investigate an abortion protester; Van Buren receives more bad news; Connie faces a moral dilemma.

The revelation of a murder victim's true identity leads detectives to a suspicious web site with threatening posts.

When a wealthy young woman is found dead in her apartment, a few signs lead detectives to believe the killer was not after her wealth; a security video exposes two potential suspects, leading the detectives to a drug cartel.

A suspicious nasal spray is found at the site of a deadly car crash; after the medical examiner realizes the spray could easily disorient its user, the detectives become suspicious of the victim's boss.

When a key witness in a murder trial is found dead in her hotel, detectives get involved in a spiraling case that unravels into an intricate conspiracy.

The team investigates a drug deal gone bad after the body of a college student is found; Detective Hailey Upton temporarily joins the team and finds her investigative methods clash with the Bureau's more buttoned-up environment.

The team welcomes a new member, Special Agent Tiffany Wallace, as they search for killers who orchestrated a mass shooting at a media company; OA's personal connection with the case threatens to cloud his judgement.

The team races to stop an active serial killer after three women are found weighted down at the bottom of a lake; Jubal looks into an old closed case after there are multiple similarities to the recent victims.

When the leader of a drug cartel and one of the world's most wanted men is apprehended by the team, the entire FBI headquarters is put at risk when his henchmen unveil a plot to free him; Isobel must make a difficult decision.

A shooting at a quinceañera leaves two dead, but the team believes they may not have been the intended targets; Maggie is conflicted as the team decides the best plan of action for using a witness to take down their suspect.

The team searches for a young girl who was kidnapped from a cabin during a family vacation; Maggie questions her relationship with Nestor when she learns he hasn't been completely honest with her.

The team must infiltrate a drug trafficking gang after the robbery of a chemical plant leaves two customs agents dead; Nestor offers his help on the case, giving Maggie new insight into his character.

On Valentine's Day, Team Scorpion must help a doctor and pilot who are trapped inside a helicopter; Toby and Happy wait for news on their fertility results; Sylvester realizes that he may have feelings for Florence.

The mental faculties of the geniuses of Team Scorpion are impaired while trying to prevent the creation of a black hole; Paige must simplify the science for them; Florence and Sylvester grow closer when she helps him with a special project.

The team is taken hostage when it inadvertently crashes a bank robbery in progress; Sylvester's feelings for Florence grow.

Team Scorpion heads to the bayou to track down a cagey alligator to stop a deadly virus; Paige teaches Walter the concept of the "white lie"; Walter hits Cabe with a tranquilizer gun, and Toby must save his life.

Team Scorpion must use their high IQs to win a softball game; Walter's secret night out with Florence puts Toby and Happy on edge.

Paige's maternal side goes into high gear when an unconscious boy gets stuck in the wheel well of an airborne airplane; Walter's white lie to Paige starts to take a toll on him; Paige realizes something is amiss.

The BAU team heads to Portland, Ore., to investigate a chilling abduction that may be linked to a local couple who were killed in their home a week earlier.

The BAU team flies to Iowa to investigate the disappearance of three 10-year-old children who appear to have been abducted from their homes, with surveillance video from a park as their only lead to finding the children's whereabouts.

Rossi questions his actions in the aftermath of a struggle with a serial killer who appears to have outsmarted the BAU.

The BAU investigates a string of murders taking place in supposedly haunted houses in Lewiston, Maine.

Rossi prepares to marry Krystall; the team investigates a series of fatal shootings following car accidents.