Lone Starr & his half-man, half-dog co-pilot, Barf the Mawg, are content to scour the galaxy living the easy life. But they reluctantly come to the rescue when Druish Princess Vespa is threatened by the evil Lord Dark Helmet, who wants to steal all of the air from her planet, Druidia. Trapped on a harsh desert world with Vespa and her robot chaperone, Dot Matrix, Lone Starr & Barf are helpless to prevent Helmet from kidnapping the girl. But assistance arrives in the form of Yogurt , a wizard who turns Lone Starr on to a mysterious power known as The Schwartz. Catching up with Helmet just as he's transforming his spaceship into a giant vacuum cleaner in orbit around Druidia, the reluctant heroes stage a dramatic showdown. The large supporting cast includes Dick Van Patten, Jim J. Bullock, & the voice of Dom DeLuise.