Mitch and Tanner visit Shark Island and a mysterious man who lost his son there appears in front of Tanner. Meanwhile, the lifeguard team performs a big mistake when assisting the Coast Guard in a rescue, which leads to a new kind of training for the team. Allie meets Nick Montgomery, a rescue swimmer working for the Coast Guard, and finds him fairly attractive. Kekoa flirts a lot with J.D., which pisses Jessie off completely. Later on, Sean tells Jessie about his attribution to nude swimming, and she decides to try it. After a while, a swimmer nearby gets in trouble, and Jessie has to save him. In the end, they returned to the new training involving the Coast Guard. Jason is chosen to wear blacked out swim goggles because Sean finds him to self-reliant. He then gets placed on a cliff without knowing where he is. By accident, Sean, who's hiding close to Jason to make sure that he's safe, gets a rock in his head and needs a Coast Guard rescue. Jason has to take of the swim goggles and help him, even though he knows that he might lose his job by doing so.