The mother of Horatio's child surfaces and becomes a prime suspect in her husband's murder. She also comes under suspicion when the witness in Horatio's son's trial suddenly disappears before she can testify.
The bride of a baseball star is shot on her wedding day. Suspects include his best friend and teammate, his bodyguard, and his agent. However, CSI discovers that the bride was not the intended target.
The body of the witness Julia Winston paid off in Horatio's son's trial is found in a swamp, but Horatio's investigation is interrupted by his extradition to Brazil to face murder charges. Meanwhile, Calleigh is kidnapped.
Calleigh's kidnappers use her to try and cover up a shooting death that they committed. However, she discovers that the gunshot is not what killed the victim. Meanwhile, CSI uncovers more clues in the death of the trial witness.
The team believes that it is dealing with a vigilante when two murder victims turn out to be pedophiles who were exposed as predators on a television program.
The team finds a body in a sinkhole, which turns out to be related to an underground bank robbery. The case also involves an incriminating video of a wealthy businessman's daughter with a drug dealer.
A notorious private investigator becomes a central figure in an investigation into a phony 911 call that ends in death, and he uses information he's gathered about Calleigh and Eric to get them thrown off the case.
A man falls to his death from a skyscraper window, and the new M.E. is shot and killed at the scene. The crimes are soon connected to ammunition dealers, an ATF agent, and Horatio's son Kyle's new stepfather.
With the help of Wolfe and an ATF agent, Horatio stages his own death as part of a plan to get Ron Saris and a shipment of fused-alloy bullets off the street.
As the team investigates a bomb explosion that killed a 17-year-old girl in a clothing store dressing room, Horatio discovers that Julia Winston and Kyle are facing new troubles.
A tanning butler is found murdered in a hotel bed next to a housewife-prostitute. However, the woman claims that she was drugged and has no recollection of the crime.
A baby girl is stolen from her mother in a crowded area in broad daylight, and the investigation takes an unlikely turn when CSI discovers that the mother's husband is not the biological father.
A sadistic killer of young women strikes again, one year after the original crime. However, CSI soon discovers that the trail may lead back to the police officer who investigated the original crime.
While investigating a homicide at a seedy motel, CSI discovers that Delko has been staying at the hotel and may have been the target of a shooting himself.
A reformed gang leader recently out of prison offers to help Horatio bring down his gang from the inside after it is suspected to be involved in the death of a community leader.