Technicolor and tights. In the days of King Henry IV, stalwart young Myles of Crisby Dale, and his sister Meg, have been raised as peasants, without any knowledge of their father's true identity. They are sent Mackworth Castle by their foster father with a letter to Lord Mackworth, urging him to take in Myles and Meg as wards. There, Myles is smitten with Mackworth's daughter, Lady Anne, incurs the enmity of the chief knight-in-training, and is assigned by Lord Mackworth to train for knighthood, himself so that he may claim his birthright and assist Mackworth and the stalwart Prince Hal in defeating the evil Duke of Alban, who plots to usurp King Henry's throne.