A cheesy rubber-suit monster flick from Wisconsin -- where they should know a thing or two about cheese. When a lazy local begins fishing with dynamite in scenic Bog Lake, something a bit larger pops to the surface: a green, bug-eyed mutant "were-fish," awakened from decades-long sleep, which promptly begins making hot meals of any unfortunate hard-drinking fishermen who stumble across its lair. When biologist Ginny Glenn (Gloria DeHaven) discovers the creature's evolutionary nature, the local sheriff (Aldo Ray, who looks really tired of playing a sheriff) decides to employ everything from pesticides to plastic explosives to slay the tenacious beast. It is hard to tell whether the filmmakers conceived this out of genuine nostalgia for 1950s rubber-monster films like Horror of Party Beach or Attack of the Giant Leeches, or genuinely thought their monster was scary. The still-attractive DeHaven appears also in heavy old-age makeup as the local hermit -- probably the producers' attempt to keep the film's only legitimate actor on screen as much as possible.