Killer alien monsters, a strange planet and spaceships all on a budget of about $150. That was the Roger Corman way and it’s only part of the charm of this tense and sometimes gory little sci-fi horror job that learned a few lessons from Alien. Some of its other fine points include a cast of cult favorite actors, from Sid Haig to Ray Walston to a pre-Freddy Robert Englund to Grace Zabriskie almost a decade before she was Laura Palmer’s mother in Twin Peaks but already looking crazy. There’s no “alien jumping out of a guy’s chest” barf bag moment here, but there is one weird rape scene between a slimy worm beast and the shapely Taaffe O’Connell that would be disturbing if it wasn’t chopped up so as to avoid an X-rating. Legend has it that producer Corman stepped in for director Bruce Clark and took over direction for that brief sequence himself because he promised a sex scene to the film’s financial backers (who might not have had something like this in mind). This is also an early credit for James Cameron as production designer and second-unit director. Cameron impressed everybody here when he famously figured out how to make maggots follow direction via an electric current.