After Mac is nearly killed trying to apprehend a criminal, he decides to tackle a cold case involving a double homicide and child abduction during a bodega robbery.

After Raymond Harris retaliates against Mac and his retired first partner, Mac begins to discover more about Harris's motives and his ex-partner's dirty laundry.

While the team stumbles upon a missing person case while investigating a murder, Mac has a brush with an ex-con whom he and his first partner put away many years earlier.

While the team investigates the explosion of a gourmet food truck, Sheldon's new relationship could get him in big trouble at the lab.

Det. Josephine "Jo" Danville's adopted daughter, Ellie becomes a key witness in a murder investigation.

CSI uncovers plenty of inappropriate behavior at one of New York's most prestigious prep schools after one of the school's brightest students is murdered.

A troubled woman who once turned to Mac after witnessing a group of men trying to cover up a murder, turns up dead herself under very suspicious circumstances.

When a serial rapist is found murdered, restrained in the same manner as his victims, the CSIs weigh a feeling of justice against their sense of duty to pursue the killer.

When the CSIs track down a suave and charming hitman, their investigation uncovers a conspiracy with far-reaching implications.

An exclusive party in the back of an 18-wheeler ends in death when the driver sends the vehicle into the Hudson River, and the team tries to figure out what happened. However, a mobster whose daughter was killed may beat CSI to the killer.

Mac is forced to work with a Barcelona detective to find out if the death of a Spanish man in New York city was a homicide or suicide.

After a man dressed in a clown costume kills a bakery owner, the evidence is soon connected to a man from Flack's past who reluctantly agreed to join witness protection to testify against drug dealers.

A department store manager is found dead inside his store's holiday window display, and the prime suspect in the case, one of his assistant managers, refuses to say a word during her interrogation.

After the woman who assumed Chief of Detectives Carver's deceased sister's identity turns up dead, and the evidence continues to mount, Mac begins to suspect that Carver may have been responsible for both murders.

As the CSIs investigate a case involving a woman who appears to have been scared to death in a supposedly haunted section of Central Park, Mac stumbles on another dead body buried nearby in the same part of the park.

Mac is on the hunt for a sniper who is using nitroglycerin in his bullets to explode on impact, and the prime suspect was once a missing boy from one of Mac's old cases.

A married couple is led to believe that they have found their badly decomposed dead son in a car on the roof of a Wall Street building. However, further investigation reveals that the victim is one of the boy's college classmates.

The team tries to find out who is responsible for a jewel heist at the home of a powerful defense attorney. However, they soon discover that everybody who comes in contact with the jewels is turning up dead.

A Puerto Rican gang leader that Mac helped put in prison many years ago is released, and suddenly the new leaders of the gang begin turning up dead.

A mother identifies her son as the attacker in a brutal assault that left her seriously injured and her husband dead. But later she recants her positive identification, and another unrelated person confesses to the crime.

Adam witnesses a murder during a random video chat, and the team discovers that the victim just so happens to be a music student who lives in Manhattan.

CSI's newest employee stumbles upon a dead body in the crime lab, while Lindsay struggles to cope with the circumstances behind her commendation.