During Vegas' latest Heat wave of triple digit temperatures, Gil and Catherine investigate a baby locked in a car. Warrick investigates a man's death of an apparent heat stroke in his house. Nick and Sara investigate a woman's body found floating in the lake with a blow to the head.

A severed head is shipped to Dr. Robbins from Jackpot, Nevada. Grissom goes to Jackpot to find the rest of the body and gets very little cooperation from the locals. Catherine gets an unexpected gift from her father.