In 1995, Donnah Winger was beaten to death at home by an intruder with a hammer. Her husband, Mark Winger, heroically shot the intruder. But four years later, Donnah’s best friend revealed to police that she and Winger had been having an affair and that he had talked about killing his wife. “48 Hours" Correspondent Richard Schlesinger reports.

This classic "48 Hours" episode last aired on 9/5/2009. Watch all-new episodes of “48 Hours” on Saturdays, and stream on demand on Paramount+.