Biker gang leader Kisum (Adam Roarke) loves waitress Marcia Little Hawk (Joanna Frank). Her brother Johnnie Little Hawk (Robert Walker, Jr.), the leader of a group of American Indians disapproves. At various times these two groups are adversaries and allies. The two groups join forces but crooked businessmen scheme to have them at each other's throats again. The theme song "Anyone for Tennis" is by Cream. The Iron Butterfly are heard playing their classic "Iron Butterfly Theme." Producer Dick Clark and director Richard Rush made "Psych-Out" earlier in the year.

"The roar of their pipes is their battle cry... the open road their killing ground!"