The team must find out if one team’s fun led to murder in the New York version of the Iditarod. Another case involves the death of a kidnapper in an empty apartment and where is the kidnap victim?

On the very night that he wins a D.J. competition, DJ Banner is found dead in an alleyway outside the club where the contest is being run, prompting Mac and Flack to investigate not only the club but also Banner's primary competition, who was jealous that his girlfriend's voice was part of Banner's act. Stella and Danny investigate the death of fashion designer Deborah Gayle, found face-down in the pool at her apartment by her assistant, who isn't concerned by her boss's demise. An autopsy reveals that the cause of death was poisoning by tetrodotoxin, a poison found in blowfish, which leads Stella and Danny to Fuqua Sushi.

Stella and Aiden investigate after finding the body of a teenage girl in a creek. They soon realize that she was a middle-class girl attending a fancy school who was trying to make it seem like her family had more money than they did, and trace her movements to a nightclub. Mac and Danny investigate when a body is found in the tunnels without any protective gear on, and end up running into a brick wall when the Sandhogs union blocks many of their attempts to get information about the victim.

Danny and Mac investigate after a briefcase belonging to Luke Sutton is found left in the NYMEX with a bloody note inside. Their investigation into Sutton's activities lead them to Nick Lawson, whom Sutton had been investigating for illegal trades, but who swears he had nothing to do with his disappearance. Stella and Flack investigate the death of Trina Rolston, a young pregnant women who fell to her death from the roof of a church. With Hawkes help, Stella realises that the body was thrown off the roof to mask the true cause of death. The detectives soon realise that their two cases are connected.

Mac, Aiden and Flack investigate when Elaine Curtis is found dead at a dog competition, a knitting needle sticking out of her chest, and no shortage of suspects ranging from judges to trainers to contestants. Stella and Danny investigate the death of bicycle messenger Michael Starling, but the crime scene may have been anywhere along his route.

Mac, Danny, and Dr. Hawkes investigate the death of a runway model who collapsed during a fashion show. Meanwhile, Stella, Detective Flack, and Lindsay investigate a teriminally ill patient's confession to the murder of his doctor.

Danny is on his way home after a long shift and finds Randy Williams subway surfing. Mac and Lindsay arrive on the scene and begin to wonder if Randy Williams died from riding on top of the subway. His death is even more suspicious after they examine the body more closely.

Stella is invited to an art gallery where she sees several paintings done by an artist named James Golden. Stella thought she was going to Frankie's place and not to an art gallery. Outside the exhibit two people are kissing and one of them is shot in the back with an arrow.

Can knowing a secret be a motive for murder? The CSI team must figure out if a change in gender is cause for the death of a showgirl. Also Lindsay goes back to Montana to try to put the person who committed the murder of four friends behind bars.

Two cases. One involves multiple homicides at a restaurant and the other starts with an amputated leg found in a dumpster.

When the charred bodies of two men who had been robbing a Chinatown bank are found, the entire team investigates the crime, which leads them to Doris, the missing infant of the bank's manager. The team realises that Joanna Cho assisted with the robbery out of fear for her daughter's life. Mac and Stella finally manage to track down the third robber, only to find him lying in a pool of blood, with a trail of bloody baby handprints leading away from the body.

After mounted officer Valasquez is shot down in the park, Mac goes looking for the bullet that killed the officer only to learn that it is lodged in the horse's spine and cannot be removed without being fatal to the horse. The investigation leads them to a local street vendor, but stalls when the D.A. asks Mac not to do anything to risk the horse until after the woman who donated it has a chance to say goodbye. Aiden investigates the body of a young man, Lenny Starks, who was found face-down, dead in the street. Aiden traces the young man to a local pizza parlor where she faces intimidation from the bookies who use it as a gambling front.

A woman's death leads our detectives to a school for sexual fetishes such as bondage and spanking.

Three cases. A murder during the Feast of San Gennaro with ties to a financial services company. A body sitting upright on a Central Park bench. An apartment fire where a 10-year-old boy died of smoke inhalation.

Mac, Stella and Flack investigate the death of a young dancer who recently won the lottery, and it isn't long before they realise that her death is connected to Lindsay's investigation concerning the death of a tram driver. Danny and Hawkes look into the murder of a local fish merchant, and soon find their way to a jealous friend who was angry that their child didn't get into a prestigious school.

When a man is found murdered in an elevator, Mac, Flack, Danny and Lindsay investigate a world where very young girls enjoy sexual encounters with much older men. They're left trying to determine whether their best lead is a suspect, a witness ... or the intended victim. Stella and Hawkes investigate the death of a young man found in Central Park who died from an extreme allergic reaction and learn that he had been pretending to be someone that he wasn't.

Mac and Stella work on the case of a female roller derby player. Danny and Hawkes look into the murder of one of New York's upcoming crop of writers.

A man dressed in a superhero costume is found dead in an alley, after saving a man being mugged. Mac, Stella, and Dr. Hawkes find his clothes in a nearby phone booth. Danny and Lindsay investigate the murder of an NFL first-round draft pick, known as "Superman."

Two women both claim to be the wife of a murder victim surprise Mac and Stella at the circumstances of their relationships. Both women have been in a trinogamous marriage with the victim. Meanwhile, Danny and Lindsay investigate the murder of a young woman who is found off a dock tangled up in kelp while she is dressed as a mermaid.

The body of a man is discovered on the Brooklyn Bridge, and the only evidence is a huge marriage proposal in lights. The CSI team works through the investigation as they learn to deal with a new medical examiner.

Danny and Lindsay examine the murder of an ice princess at a vodka release party while Mac, Stella, and Don examine the death of a runner at a Marathon in Central Park. Both crimes have interesting problems the teams must overcome to find out how they both happened.

The CSI's handle to puzzling cases; Carensa is a young Suicide Girl who at 17, wanted a change of scenery and to become a Suicide girl, at 18 she gets her wish only to lose her life. Chopper, a rising street basketball star, a homeless man trying to change his life for the better is killed and leaves a painful trail of blood which leaves Mac to figure out where and how he died.

A young woman dies after she starts bleeding from the eyes, nose, and mouth while at a party aboard a subway train. Mac originally believes she is the victim of a biological attack. Later, it is revealed that Sheldon knew the victim. Across town, a wealthy playboy is found dead in an indoor lap pool in his penthouse suite. The investigation reveals that he was murdered and his last maid was fired two days earlier.

The team must figure out how a self-cleaning restroom leads to a drowning. The team also investigates the death of a man who was set on fire and flew into a fire truck.

When an unidentified shooting victim turns out to be a rising star in the underground world of hip-hop dance battles, the CSIs turn their attention to a long list of rival dancers.