While in a dinner party to celebrate the retirement of Director of Robert Cavallo and the promotion of Conrad Ecklie, Grissom is summoned by Capt. Brass to investigation a homicide in the Olympia Hotel. He stumbles upon Ecklie's right hand Sofia Curtis in the elevator and they go with Brass to the suite where they see the body of the teenage Nicole Jensen next to vomit. Soon they learn that the suite was reserved by the hotel's owner Charlie Macklin for his daughter Janelle. The McKinley High School is giving a homecoming party in the ballroom, but Janelle is giving a private party in the suite. Catherine, Nick and Warrick join the investigation and interview the guests. They note that Janelle is missing and they learn that two masked kidnappers have abducted Janelle. When Catherien and Sheriff Atwater interview Charlie, he tells them that he knows his daughter and that was a prank to get his attention. The CSI team proceeds the investigation and find the truth of what happened during the night.

Someone tries to kill a diva called Lois O'Neill, who was related to the mafia years ago, and a waiter is killed instead. The CSI investigates the case, but more than ever, nothing is what it seems.