Beryl is a hooker who guards her territory viciously. When another prostitute challenges this, she has her two faithful goons, Harp and Logan, rough the newcomer over. Before things get too serious, however, the four individuals are incapacitated and taken to a spaceship by a man named Wodro.This man divulges that he is an alien from a distant planet, and that he wants Beryl to kill the other hooker right before his eyes. She agrees with eagerness and crushes the blonde prostitute's head with a nearby vice. Satisfied with the results, Wodro goes on to explain that on his planet, victims of crimes are allowed to carry out the death sentance, personally, against the perpetrators. In his case, it is his wife, Yzin, who made an attempt on his life after she caught him cheating on her. Wodro is so furious at his spouse that he wants her to suffer the worst death imaginable, and offers to pay Beryl, Harp and Logan 200 pounds of gold if they help him discover what that is. The woman and her two friends have no scruples with saying "yes".
After abducting and killing over fifty women, Beryl is shocked to find that Wodro still has not witnessed what he is looking for. Taking a walk, she is contacted privately by a man, Mirsho, who claims to be Yzin's brother. He then promises to triple the reward that Wodro has in store, if she changes her plans to aid him instead. Using specific instructions from Mirsho, Beryl creates a chemical concoction that causes unbelievable suffering to the next captured victim in the queue. Overjoyed to have finally found the results he was after, Wodro gives the three Earthlings their gold and returns them to Chicago.After some prodding by Harp and Logan, Beryl reveals that she actually gave Wodro "false" instructions. It is true, as back on Wodro's home planet, the execution is a failure, giving Yzin only a slight tummy ache. As local laws legally prohibited anyone from attempting to carry out a sentance a second time, the male alien is devistated to see his released as a free woman. Mirsho gloats about what a sucker his brother-in-law is, and is more than happy to explain exactly what went down.
Back on Earth, Beryl, Harp and Logan are living it up in their new mansion, when Wodro pays a surprise visit. The alien kills the two men using his ray gun, but when attempting to do the same to the woman, the beam reflects back off of her body, mortally wounding Wodro. Beryl divulges that she is wearing a piece of invisible armor, given to her by Yzin and Mirsho, and thanks the alien for killing her two partners, as she was annoyed that she'd have to share two-thirds of the gold with them.
Her revenge complete, Yzin is about to part ways with Beryl when the Earthling casually admits that she had sex with Wodro during the time they were acquainted. Despite the fact that her husband is now dead, Yzin's jealous nature comes to a boil and she then murders Beryl by carving her up, piece by piece, with her ray blaster.