Watch Young Warriors (1983)

One of the greatest 80's movies you've never seen, Young Warriors is about a psychotic animation major whos little sister is raped and killed. He must recruit his frat brothers to create a vigilante group to find and kill the evil gang who killed his sister. Watch it now. Seriously.

"Meet the ultimate weapon in the fight against crime!" First they killed his sister - now he's out to get even! Keith Carrigan, policeman's son, is joined by his friends and sets out on a campaign of vengeance. They used to be clean-cut American kids.