Siblings Lonnie and Tobe live at the edge of the bleeding sprawl of the San Fernando Valley. One day, a mysterious horseman strolls into their lives. With his folksy-naïve manner and cowboy garb, Harlan Fairfax Carruthers initially evokes a bemused "Are you for real?" from one of their friends. But to Lonnie and Tobe, Harlan's alien behavior seems to be exactly what they need.