Season 12

After multiple attacks on a public tram, the team has just one witness and a lot of questions.

When three people confess to killing a family, the team must decide who is telling the truth.

During a date, Stokes discovers decomposing body parts in part of an art exhibit; D.B. Russell deals with a staff member confrontation.

The investigators attend the gala grand opening of a mob museum, only to witness an attempted hit on mob lawyer and former mayor Oscar Goodman.

The CSI unit investigates when Frank, an apparent murder victim, sits up and needs help but is he just another victim?

The murder of a popular sideshow performer sends the team behind the scenes at a carnival freak show.

The CSI crew is stumped when they discover a disembodied brain at a crime scene where all the other brains are accounted for.

Three new murders related to three unsolved (or incorrectly solved) crimes from the past come back to haunt the CSIs.

The murder of a retired Army Ranger brings the FBI in on the case, to Russell and Catherine's initial chagrin.

When a man's dead body turns up naked in the bed of Doc Robbins' wife, the detectives try to "just work the scene" without bringing their pre-judgments to the table, but it sure looks like a case of Death During Adultery.

Catherine's friend Laura's mogul husband Mark has a lot to hide behind his successful international corporation, and he's hired a crack team of assassins to carry out the murders of anyone who might be aware of what he's doing, and that includes Laura's lawyer and Laura herself.

The CSI team says goodbye to Catherine Willows as she makes a life-changing decision.

When a woman is found dead and her hair is done up '70s style complete with vintage clothes, the CSI team discovers clues that point to a killer with a hair fetish.

Russell seeks advice from a former colleague during an investigation into the death of a man's ex-girlfriend.

When a house is stolen completely off its foundation, the CSIs are on the case in search of answers. Meanwhile, new CSI Julie Finlay showcases her skill in blood analysis.

When a blackout cripples the city, the CSIs must revert to old-school methods to solve the case of a missing child.

When a photo of a dead college student starts trending on the Internet, the team steps in to investigate.

The team has few leads to go on when investigating a robbery-homicide at a themed wedding

When the CSI team is called in to investigate a man who is shot at point-blank range in a local casino, they shut down the entire building to find their killer.

When Stokes learns that a man he helped put in prison is going to have his conviction overturned, the CSI team needs to prove the killer is guilty again or he will be released.

When a bomb kills an off-road race truck driver mid-race, the CSI team is called on the scene to investigate why.

Season finale: The investigation of a triple homicide leads to the discovery of corruption running rampant throughout the LVPD. The closer they get to the truth, the more serious are the repercussions. To be continued...