fisher became very jealous of joey buttafuoco's wife. fisher then got a .25 caliber handgun. when the wife answered the door, fisher told her that joey buttafuoco was having an affair with fisher's (imaginary) younger sister. the conversation lasted 15 minutes. mary jo got angry. she then told fisher to leave and turned her back to return to the house. that was when fisher took out the gun, struck mary jo with it and shot her in the head. fisher dropped the gun and the shirt. she came back for them.