Space Thing (1968)

A man, named James Granilla, is in bed reading Sci-Fi mags, and his frustrated wife Marge seduces him. He then falls asleep, and the rest of the movie is a dream. In his dream, James is from an alternate world who disguises himself as an alien, then boards their ship, to keep them from attacking his planet. The captain is a woman, who has two lesbian encounters with her female crew, named Connie and Portia, and whips one of them for trying to have sex with our hero. All of the women are anxious to seduce James, as the other two men on the ship, Willie and an unnamed cadet, are not very exciting. James forces a landing on a large asteroid (actually the outskirts of Palmdale, California) and everyone runs around topless and has sex with each other. He ends up blowing up the alien ship in the worst special effects explosion in film history.