When King Richard the Lionheart is captured, his scheming brother Prince John (Claude Rains) plots to reach the throne, to the outrage of Sir Robin of Locksley (Errol Flynn), the bandit king of Sherwood Forest. Rounding up his band of men and eventually winning the support of the lovely Maid Marian (Olivia de Havilland), Robin accuses Prince John of treachery and, when the escaped Richard returns covertly to England, joins forces with the king to prevent Prince John from taking the crown.