Hysteria ensues when a shark attacks a woman in the pool of a Las Vegas Casino while hundreds are attending a very popular "day club". CSIs are called in to figure out how a Tiger Shark got into a Las Vegas casino pool. The casino owner, Earnest "Booze" Boozell, has had a long-standing rivalry with another casino owner, Danny Macklin, whose "day club" across the street is Booze's competition. Langston and Dr. Robbins notice that the victim's flesh is white not pink at the point where the shark attack occurred and realize she was dead prior to the attack. A puncture wound in the victim's back and surveillance video lead the team to a career thief who drugs her victims before robbing them. This time she unintentionally gave the victim a "hot shot" and killed her before she robbed her. The question still remained - how did a shark get into the pool? Langston examines the shark with the Aquatic Veterinarian Dr. Holloway and realizes Holloway is lying to them about the shark's origin. Before Catherine can interrogate him, he is murdered after someone tampered with his scuba gear. The evidence leads to Booze, theorizing he may have placed the shark in his own pool in order to blame and bring down his rival. The tag number found on the shark actually showed that Macklin was the one trying to set up his rival to get him out of the way so he could make his lucrative "day club" even more profitable.

Catherine is reminded of her father in several flashbacks when Booze brings back fond memories for her since Catherine's father and Booze where friends back in the days of "old school" Vegas.