An environmental terrorist group bombs the home of an electronics recycler, and his daughter is killed--but the daughter is part of the terrorist group. Meanwhile, Danny considers proposing to Lindsay again.
A man is killed when he falls out a window in media mogul Robert Dunbrook's building, but did Dunbrook throw him? During the investigation, Mac discovers that the case is connected to an earlier case involving a missing flash drive.
Following a spray of machine gunfire, the CSI team rises from the chaos. But when one member's life is significantly changed, it proves to be the emotional motivation they need to piece together their lives and ultimately find the shooter.
While investigating the DNA from a murder scene, Hawkes discovers that the DNA is connected to more than a dozen cases over a three-state area. But does the city really have a serial killer on their hands, or is there another explanation?
When a software company executive bleeds to death on a Manhattan street, the CSIs must delve into the wet and messy world of food "sploshing" parties - where groups of people experience food in an sensual way - to find his killer.
After a body falls from the 59th Street Bridge, the CSI team finds a compass near the body pointing east, and realizes it's the third victim of the Compass Killer. Meanwhile, detective Flack, still dealing with Angell's death, goes AWOL.
Mummified remains are found in a booby-trapped Manhattan penthouse that has been closed off for more than 80 years, and Mac and Stella race against time to find the people who discovered the body, who are still trapped in the building.