The Man from the Deep River (1972)

When a group of primitives mistakes him for Aquaman, nature photographer John Bradley (Ivan Rassimov), who's on assignment in Thailand, is captured and brought back to the tribe's village, where he's expected to perform aquabatic feats like pulling turtles from the depths of the river to the surface and then tossing them into the air, all while at spearpoint. Initially Bradley wants to escape, but he soon finds himself drawn to the charms of life in the village, which include the cutting off of tribespeople's tongues and hands for minor infractions and the near-constant butchery of animals, and he decides to join up. After enduring an unpleasant initiation ritual, he becomes a full-fledged member of the club and gets to spend his days disemboweling various members of Kingdom Animalia. He falls in love with Maraya (beautiful Me Me Lay, and I'll resist the nearly overpowering urge to make the obvious joke) and wins the right to marry her by besting his competitors in a sort of tribal version of The Dating Game in which the bachelorette sits naked on the floor of a hut and the contestants reach through a hole in the wall and grope various body parts. Bradley reaches through and takes hold of her hand, and she apparently finds this more romantic than Bachelor #1's breast massage and Bachelor #2's well-meant but poorly executed attempt to pick the lice from her pubic thatch. John and Maraya get married and spend the next ten minutes or so of the film frolicking about in the nude and screwing in a bed of... flour? But a hostile tribe of cannibals and a turn of bad luck soon threaten Bradley's newfound happiness.

Also appearing under such titles as Sacrifice! and Deep River Savages, Umberto Lenzi's The Man from the Deep River was the first of the cannibal/jungle exploitation films. The violence against humans is less extreme than in many of the films that followed (there's one scene of cannibalism, which Lenzi later reused in Eaten Alive!, but most of the people in this film get off easy), but Thailand's long and proud tradition of animal torture is on full display (snakes and crocodiles are cut to pieces while still alive, the top half of a monkey's skull is hacked off and its brains eaten, the villagers entertain themselves by watching cockfights and pitting a mongoose against a cobra, etc.). When the film isn't distressing (real animal abuse is distressing; pretend human abuse isn't) it's usually fairly boring (except the scene with the elephants -- that's awesome). I don't particularly recommend it.