Attack of the Giant Leeches (1959)

In a small town, monsters resembling giant leeches terrorize the local swamp. A game warden, a sheriff, and an ecologist team up to stop them, using dynamite and scuba diving to find and destroy their lair. However, they face challenges such as a dysfunctional marriage, a cuckolded husband, and a giant mutant leech that can reproduce on its own.