The construction of the colossal Glen Canyon Dam on the Colorado River spurs an oddball quartet of eco-activists to join forces in a noble cause. A Vietnam veteran who loves booze, guns and the great outdoors, a billboard burning doctor, a feminist revolutionary and a polygamist riverboat guide – the Monkey Wrench Gang go up against the vultures of big business to sabotage the strip mines, power plants and concrete dams that are destroying vast tracts of the wilderness, through peaceful means – or otherwise …