<P> `` The Duel '' is the twelfth episode of the fifth season of the American comedy television series The Office , and the show 's 84th overall episode . In the episode , Andy learns his fiancee Angela is having an affair with Dwight , and the two challenge each other to a physical fight to win her affections . Meanwhile , Michael travels to New York City for a meeting with David Wallace , where Wallace seeks managerial advice from Michael due to the poor financial condition of the fictional company , Dunder Mifflin . </P>
when does andy find out about angela and dwight
the twelfth episode of the fifth season