While Stella meets her persistent suitor Drew Bedford for a drink, model Jenna Donovan dies in an over sized martini glass at a martini ad party in front of a Times Square billboard. The CSIs first presume she was killed by tennis balls that pelted the party at high speeds, but it turns out the alcoholic who launched the balls from an athletic research company nearby wasn't responsible for her death; Jenna was in an altercation shortly before she died that could have resulted in the pulmonary edema that killed her. The CSIs discover Jenna's purse was filled with lollipops containing a street drug called Magic and trace a piece of jewelry back to a local shop, where they find some of the lollipops. The proprietor, Pattie Larkin, admits to scuffling with Jenna, trying to get to the drugs, but she claims she left Jenna alive. Flack is ready to put her away for murder--until Sid discovers a chemical burn on Jenna's arm that could have had something to do with her death. It proves to be the key when the CSIs find small but deadly jellyfish in a beach ball Jenna was holding. Stella and Lindsay question Damien Barnes, the party's mastermind, and Lia Ramsey, another model and learn Lia is at fault, but that Damien, rather than Jenna, was her target. He stole her idea for the parties, so she planted the jellyfish in the beach ball he was going to blow up for the party, but a slit in the ball saved him and instead led to Jenna's death when she tossed the ball around.
Danny rushes to the hospital in an ambulance alongside Brandi Parsons, who was shot in the head during a robbery in Club Prowl, where she worked as a bartender. He reassures her boyfriend, Paul, while he waits at the hospital, hoping to question Brandi. But all is not as it seems when Brandi's surgeon, Gavin Moore, pulls Mac aside and tells him that his brother, Charles, has been abducted and that the kidnappers are threatening to kill him if Gavin doesn't let Brandi die. When Angell mentions Brandi's mother is dead--something that directly contradicts what Paul told Danny, Danny realizes that Paul lied to him. Surveillance footage reveals Paul outside the club during the robbery, confirming he was in on it. Semen on Brandi's clothes matches semen on the robber's mask, which another victim who didn't survive the robbery ripped off. Brandi was shot because she could identify the robber.
Hawkes links a bat bone back to the shop where Paul worked, and the owner gives the CSIs a last name for Paul: Campbell. The CSIs trace Charles Moore's cell phone back to Paul's apartment, where they find evidence of a struggle, but no sign of either Paul, his roommate, or Charles. Danny finds a mailing box with a torn off piece of money on it, and Hawkes goes through the computer cache to get the name of Paul's accomplice: James Petty. Danny isn't able to recover the address on the mailing label at first, but he comes up with the idea to bake it in an incubator oven and comes up with an address. He, Angell and Hawkes rush there and discover Paul and James with Charles and the money. Danny is relieved to tell Mac that Brandi made it through her surgery and is going to live.