The team go back to school when a college professor is murdered, with Danny posing as the professor's replacement.

A young intern at California's state capitol is found dead at the bottom of a ravine. Evidence places the woman's stepbrother in the frame for murder, but Jane suspects that the crime was politically motivated. Elsewhere, Jane offers Bosco some words of warning about Red John.

A young man is murdered over what appears to be a land dispute. During the investigation, Jane is arrested and sent to jail for bugging Bosco's office - but manages to continue probing the case from his cell.

Bosco and Lisbon reluctantly join forces to deal with a kidnapping case. When it seems as though the hostage has no chance of survival, Jane comes up with an unorthodox plan to save the victim's life but Bosco refuses to put it into action.

More positive changes are made by the hospital's new management; Meredith worries about her unborn baby; Alex decides to give Jo's boyfriend a run for his money.

As the doctors move forward with their lawsuit, they must face the realities of their injuries; Bailey tricks Arizona into assisting with a paediatric case; Cristina seeks normalcy in her new environment.

Bosco and his agents are gunned down within the walls of CBI headquarters. With two men dead and Bosco in a critical condition, Lisbon and her team race to find the perpetrator. As the investigation progresses, it becomes clear that notorious serial killer Red John is responsible - and he has an assistant inside the department.

Derek and April fight to find a solution for the hospital; Cristina works to respect the wishes of a dying boy's family; Arizona identifies with a teenager who is facing similar problems.

Lightman is obsessed with his investigation of two women who committed suicide; the team tries to recover millions of dollars for investors who were scammed.

Jackson must deliver bad news to the doctors; Derek's sister visits; Richard surprises Catherine in Boston; Bailey makes a risky decision about her research.

Jane works to solve the murder of a jogger, Jane tries to hide her pregnancy from her mother, and Maura and Frankie face the aftermath of their kiss.

The CSI team investigate a murder that happens at an obscure convention for people who collect disturbing and gruesome murder memorabilia. The main suspect seems to be the sister of another serial killer's victims.

As Magnum, Higgins, and TC try to pull one over on a customs agent to get Higgins a green card, armed gunmen suddenly storm the federal building and start taking hostages.

Jonas and the team combat a South American oil minister, while a Congressional Committee scrutinises Colonel Ryan.

Jonah finds himself in a tricky situation in the Democratic Republic of Georgia and Tiffy continues to fight her legal battle.

Philip is advised to lose weight after his annual medical. However, after a good start, he soon slips back into his unhealthy ways, with serious consequences.

Alien overseer Charles (Duncan Regehr) decides to brainwash Ham, captured along with Kyle; Diana plots to betray Lydia.

The Task Force make progress on a suspect, Poole continues to clash with Lieutenant Larson, and Biggie and Tupac find themselves at the centre of a growing rivalry.

Jake and Hawkins have just one chance to prove to the Texas government that they have evidence of one of the biggest conspiracies in history, but the Cheyenne government stands in their way.

The Task Force receive help from an FBI informant with a questionable past, Poole shares his work with Voletta Wallace, and Tupac clings to life in a Las Vegas hospital.