The newest member of the CSI team, Jo Danville, a former FBI agent, is welcomed to her new job by stumbling upon the body of a young woman murdered somewhere in the building that houses the NYPD Crime Lab.

When a young woman appears to be strangled while participating in a live online chat that Adam witnesses, the CSIs must determine if it was real or a hoax, and locate where the possible victim is.

When a married couple is found beaten in their home, a mother identifies her son as the killer and the CSIs believe they have their suspect, but all is not what it seems when another witness comes forward.

A jewel heist at the penthouse of one of New York's most powerful attorneys takes a bizarre turn and the case leads the CSIs to a seemingly unrelated man in the morgue.

When a badly decomposed body found is an abandoned car on a rooftop, Mac and his team must go up against a killer who is using the parents of his victims to manipulate crime scenes.

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.

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.

When a woman's body washes up at the South Street Seaport, the CSIs unravel a dark secret from Deputy Chief Carver's past that threatens to shatter his stellar reputation and close-knit family.

Mac and the team search for the killer of a department store manager who was found dead in a holiday display window.

When a man in full clown costume shoots a bakery owner, the CSIs investigate and discover a decision from Flack's past that may put him in jeopardy.

When a Spanish club promoter is found dead, Mac must battle with the head of Barcelona's crime lab to solve the case.

When a tractor-trailer carrying exclusive party guests mysteriously ends up at the bottom of the Hudson River, the CSIs must solve the mystery from the soggy remains.

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

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 a conspiracy-obsessed woman is found dead, the CSIs investigate and discover that some of her theories may have had some truth to them.

When a popular student and star pupil at Manhattan's most elite private school is murdered, the CSIs find themselves immersed in the highly competitive world of over-privileged youth.

Jo balances personal and professional challenges when her adopted daughter, Ellie, is the key witness in a murder investigation.

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

The CSIs investigate a woman's death as the work of a serial killer, and Mac reconnects with his first partner after an ex-con they put away begins stalking him.

After a hail of gunfire tears through the crime lab, Mac and his ex-partner become part of a vendetta 17 years in the making.

Following a near-death experience, Mac becomes determined to close his last remaining unsolved case.