A college student and former child prodigy receives a death threat and subsequently disappears while working in a mall as a department store Santa.

The team attempts to locate Scott Lucas, a private investigator who has gone missing while doing undercover surveillance.

Michael is furious when he discovers a secret that Cassandra kept from him. Alex makes a last-ditch effort to find her mother.

When a million dollar casino heist takes a deadly turn, Riggs befriends the only credible witness, an 8-year-old boy, and takes him into his care. On the flip side, Murtaugh pulls some dangerous stunts in an attempt to prove to everyone that he can be a motorcycle guy.

Tang prepares to move on to a new precinct, but first she wants to tie up some loose ends on the beat. Lydia is pressured to make a decision about her future.

Officer Cooper clashes with his new "boot" -- Gary Steele, while Lydia Adams tries to balance detective work with motherhood.

Jane suspects that Agent Susan Darcy has ulterior motives when she asks for his help with a homicide investigation. Meanwhile, the CBI team handles the murder of a young woman who was killed after meeting someone in an online chat room.

Michael is furious when he discovers a secret that Cassandra kept from him. Alex makes a last-ditch effort to find her mother.

When her former patient returns to Med, Goodwin learns that time doesn't heal all wounds. Frost and Charles treat a patient struggling with his sexuality. Lenox and Abrams work to save a woman who has been in a coma for 20 years.

When a million dollar casino heist takes a deadly turn, Riggs befriends the only credible witness, an 8-year-old boy, and takes him into his care. On the flip side, Murtaugh pulls some dangerous stunts in an attempt to prove to everyone that he can be a motorcycle guy.

Officer Cooper clashes with his new "boot" -- Gary Steele, while Lydia Adams tries to balance detective work with motherhood.

Jane suspects that Agent Susan Darcy has ulterior motives when she asks for his help with a homicide investigation. Meanwhile, the CBI team handles the murder of a young woman who was killed after meeting someone in an online chat room.

Michael is furious when he discovers a secret that Cassandra kept from him. Alex makes a last-ditch effort to find her mother.

When an ex-con who has recently been released from prison goes missing, the team questions whether her past mistakes, including embezzling money from former clients, may have come back to haunt her.

A college student and former child prodigy receives a death threat and subsequently disappears while working in a mall as a department store Santa.

When a million dollar casino heist takes a deadly turn, Riggs befriends the only credible witness, an 8-year-old boy, and takes him into his care. On the flip side, Murtaugh pulls some dangerous stunts in an attempt to prove to everyone that he can be a motorcycle guy.

When her former patient returns to Med, Goodwin learns that time doesn't heal all wounds. Frost and Charles treat a patient struggling with his sexuality. Lenox and Abrams work to save a woman who has been in a coma for 20 years.

Officer Cooper clashes with his new "boot" -- Gary Steele, while Lydia Adams tries to balance detective work with motherhood.

Jane suspects that Agent Susan Darcy has ulterior motives when she asks for his help with a homicide investigation. Meanwhile, the CBI team handles the murder of a young woman who was killed after meeting someone in an online chat room.

Michael is furious when he discovers a secret that Cassandra kept from him. Alex makes a last-ditch effort to find her mother.

The whole precinct's holiday celebrations are cut short when they're called to examine a ruthless homicide linked to Eddie Flores, the deranged nephew of a notable drug lord who has a previous history with Riggs.

When an up-and-coming politician is found dead, Shaw and Riley untangle the victim's personal life to identify a suspect; Baxter recuses himself to help Price make the case.

When a murder suspect becomes an underground hero, Brady seeks help from a former colleague to track down a culprit who seems to be in multiple locations.

As more people die, all paths seem to lead to Mark. What is the secret of The Pale Horse?

When the investigation fails to bring about extradition of Lugovoy and Kovtun, Marina begins an 8 year battle to seek justice for her husband's murder.

Jane and the CBI try to narrow down the list of suspects when a terminally ill man is found murdered. Meanwhile, Cho is forced to face his demons.