This is the 17th episode of Season 1. Aired on October 15th,2012.
Leo becomes Davenport's Lab assistant and accidentally releases a powerful virus, which results in Eddy becoming a demon named Teddy. Meanwhile, Bree has a sleepover and invites a mean girl ,Stephanie, and her friends. When Adam and Chase hear about the sleepover, they decide to prank the girls, but they interrupted when Teddy takes over, sending everyone into a panic.