A tour group visiting a preserved building at Ellis Island finds a dead man who seemed to have hung himself, but the CSIs uncover that the man died about 8 hours ago, but managed to answer a call from his wife a few hours after his death, which confuses the team. However, when a crime on the other side of the city is similar to this one, and both cases have a compass lying next to the victims, the team suspects they are dealing with The Compass Killer.
Mac and the CSIs investigate what really happened when a software company executive bled to death on a street, but Hawkes has problems concentrating on the case when it turns out the victim is someone he knew and could’ve saved. Therefore, Mac and he start their own little investigation into the case.
In the last episode featuring the Compass Killer, the CSI team stops at nothing to get their man, and they have uncovered a large area in which the Killer is at. While Mac and Don search the Killer’s lair, he is planning his next victim, and the team now has to fight against time to find the Killer and bring him to justice before he kills another innocent person.
It’s Christmas time in New York City, but the CSIs aren’t getting their vacations yet, as they need to first solve a crime in which a young man was found dead in an alley brutally killed, or so it seems. Further investigation proves that the victim was only struck by a car, but he has a history of being a former drug addict, with a large amount of heroin in his system before his death. However, the investigation changes when the CSIs uncover a $2.5 million dollar insurance policy, as one of the suspects is the victim’s girlfriend, who cashed in on the insurance, making it an insurance scam of the worst kind.
Songs: Train -- Calling All Angels, Train -- Hey Soul Sister
A star quarterback of the Lingerie Football League is found murdered in the team's locker room hot tub. The investigation finds that the victim had lidocaine in her system, leading them to try to figure out who in the organization wanted her dead.
A racing legend dies two days before a Grand Prix Race in an explosion in Manhattan. The CSIs find that the car that exploded had been tampered with, and their investigation takes them into the world of racing and beyond.
On the night of a young man's 21st birthday, his friends take him out to celebrate, but when they turn up dead and he's found walking in the middle of the street covered in his friends' blood and wielding an axe, the CSIs must trace the events of the man's wild night to figure out just what happened.
Stella has a hard time convincing the team when a murder that looks like a suicide is being investigated, so Stella does her own investigation into the case.
A death row inmate's final request brings Dr. Hawkes to a Pennsylvania prison and face-to-face with a tragic incident that he has kept secret for many years, just as a prison riot erupts and traps Hawkes inside
When a slab of concrete starts bleeding in midtown, the CSIs' investigation takes them into the underground world of hardcore fighting, where men moonlight as "weekend warriors" for the pleasure of a live viewing audience.
When Mac and Aubrey come across the scene of a 14-year-old boy who has been shot in front of his 12-year-old brother, it takes Mac's drive for justice to another level.
The CSIs follow a trail left by Shane Casey and realize that he is targeting Danny, who is vacationing out of town with Lindsay and their daughter