A mysterious figure called "The Phantom Lifeguard," begins making rescues and disappears before being identified by anyone. While Mitch thinks the Phantom Lifeguard is an outsider, Cody and J.D. think the unseen hero of the day is getting his/her information from inside the department. Meanwhile, Ed Symes, the obnoxious and annoying medical supply salesman, returns and tries to get on the good side of Mitch and Alex by riding around with them for the week, and he causes nothing but trouble for everyone as usual. Also, Alex hires Jessica "Jessie" Owens, a new maintenance person and movie stunt woman for Baywatch headquarters. Jessie is inept at keeping things in order, but shows off her physical strength during workouts and it soon becomes apparent that she may or may not be the Phantom Lifeguard.
- New castmember Brooke Burns makes her first appearance on the series as Jessica "Jesse" Owens in this episode.