This production from the infamous Joe Levine is a familiar saga - an adventure yarn that recycles the worn-threadbare cliché of a party stranded in the wilderness and attempting to survive, to so-so effect. But it has one running thread throughout that touches the sublime: as the marvelously-named Brian O'Brien, B-movie favorite Stuart Whitman gets to play someone so sadistic, vile and nasty that one can't quite believe his actions. This psychopath's favorite pastimes consist of picking off innocent animals with his gun, torturing baboon chimps with fire, and attempting to strong-arm several other members of the expedition into the grave. Acting like the love child of Charles Manson and Bobby Berosini, O'Brien is an outrageously sick character, and the screenwriters use all of his ills against animals as narrative plants, over the course of the movie's running time. His evil actions build up to one of the most shocking conclusions in B-movie history, as nature itself turns on this sadist and asserts its anger in the most violent and retributive of ways. The surrealistic final sequence (which begins with a Whitman line that foreshadows Roy Scheider's "smile, you..." line in Jaws, and concludes with an image that may have inspired the last shot in Herzog's Aguirre: The Wrath of God) is nothing short of spectacular entertainment, and arguably makes the whole journey that has preceded it worthwhile.