Baywatch (1989)

S11E19 Trapped

Sean and Leigh find themselves in serious jeopardy after they save two surfers stranded on a reef in Maui, where one of the surfers suddenly falls ill. Sean's instincts kick in, leading him to suspect that the illness might be linked to the reef itself. As they dig deeper into a local company, they are captured by a corrupt department head who aims to silence them and hide the truth about the toxic chemicals used to fabricate a man-made reef.