Power Rangers Lightspeed Rescue: Neptune's Daughter (2000)

Chad's lovesick, but not just for any girl. He's fallen for Marina, daughter of King Neptune, and one of the loveliest mermaids in the sea. Of course, that makes Vypra absolutely delighted. Now she can use the unsuspecting Marina to capture Chad and keep him prisoner forever! Vypra sets her trap and things are looking bad! First, she has the Aquafiend monster steal King Neptune's trident. This makes all the water in the city begin to drain away. Marina must ask Chad for help. When she does, Vypra captures her! Now Chad must choose between saving Marina and saving the city!