Bad Influence (1990)

Michael is a sheepish person who is pushed around by everyone. He meets Alex, who teaches him to be assertive and indulge in risky behaviors. Things go too far when they go on a drug-fueled robbery spree and assault Michael's work rival, and when Michael wants out, Alex becomes angry. He steals all of Michael's possessions and frames him by killing a woman in his apartment. Michael's new-found sense of self-preservation helps him fight back with the help of his brother.