This paranoid 1975 actioner by Gordon Parks, Jr. (Super Fly) concerns a white supremacist plot to cleanse America ethnically by poisoning the water supply in three predominantly black urban areas. Parks has assembled a dream team of the blaxploitation genre—Jim Brown, Fred Williamson, and Jim Kelly—to fight back and save the race. Like many other conspiracy thrillers of the era (e.g. The Parallax View), the movie uses cold industrial and urban environments to convey the long odds the heroes face; other elements, such as the trio of topless female bikers brought in to torture one white supremacist, nudge this toward Russ Meyer territory. There’s rarely a dull frame.