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.

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.

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 and Stella investigate the murder of a woman who was stabbed in the heart with a wooden stake. The police arrest a woman who was kneeling over the body with blood on her, but Mac isn't convinced that she committed the crime.

When the chief investigator of a controversial report documenting corruption within the NYPD is gunned down the day before his findings are published, Mac and Stella must find the killer, launching a massive search that makes every officer listed in the report a suspect. Meanwhile, Danny and Aiden investigate the murder of a gypsy cab driver.

The team examines the murder of an avid Boston Red Sox fan found dead with a ruptured spleen following a tough loss against New York. Danny must put his baseball skills to the test to piece together the evidence as the CSIs try to find out how and why he was murdered. Meanwhile, after testifying in a murder trial, Mac is confronted by the defendant, Quinn Sullivan, who questions the validity of the evidence. Mac is torn between trusting science or his desire to help a man facing jail time who swears he's innocent. Also, when a truck kills a barely clad woman early one morning, the team investigates why she was running through the streets and from whom.

While Mac dines at his local breakfast spot, a gunman opens fire, leaving a waitress critically injured and a man dead, and Mac having to choose whether to chase after the suspect or save the life of the young woman. Meanwhile, before the chaos, Mac was approached by a shy patron who awkwardly engaged him in conversation. After feeling that he saved her life during the shoot out, she asks him to join her for a drink and Mac must decide if he is ready to start dating after his wife's tragic death.

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 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 young boy witnesses the death of a museum curator but doesn't want to tell anyone about it. Danny investigates the death of an urban golfer found dead on a construction site.