A vicious space-outlaw, Zeiram, has escaped to earth, and has been followed by the attractive female bounty hunter Iria, and her assistant, Bob (a computer). When she sets a dimensional trap so she can fight the monster without raising the awareness of the earthlings, two power company employees accidentally stumble into the trap, too. Iria now has to save the earthmen and defeat the monster before her Dimensional trap closes on them all forever.