An underwater photographer named Linda is attacked inside a sea cave. Her boat is destroyed and her partner Walt ishuged. Mitch rescues her. Because she doesn't know what attacked her, everyone think it's a sea monster. When Linda talks to Devon, another lifeguard, she can't give her any good information about what really happened down there.
This long-running series follows the adventures of a team of lifeguards on the crowded beaches of Los Angeles County. Veteran lifeguard Mitch Buchannon watches over the younger lifeguards that come and go with each passing season as they keep the beaches safe for vacationers. Frequently he must take action to save them from the raging seas and from the raging tempers that sometimes flare up between the young guards in this stressful job.