Mitch's upcoming birthday motivates him to enter an iron-man competition. He needs to show he can still compete with younger men. Meanwhile, Matt's effectiveness as a lifeguard suffers due to his new night job. His late hours make Summer suspicious since she doesn't know about the job. Standing in for a tired Matt, Summer is knocked unconscious attempting a rescue.

Gymnast Mary Lou Retton, a long-time friend of Mitch, asks him and the Baywatch lifeguards to help organize and host a Special Olympics, an athletic competition for developmentally challenged youths.