Debonair David Niven is a noble scoundrel in this romantic, swashbuckling drama of royal intrigue inside the court of Charles II. Niven plays the Duke of Brampton who, though trusted by Charles, is actually planning to overthrow the shaky Restoration monarch. But, despite careful scheming, the Duke is in for a few surprises: the brainy and vengeful Lady Mary (Ann Blyth) and the infamous highway robber Michael Dermott (Edmund Purdum) - the one man in England who knows what Brampton's up to. These two are formidable foes indeed, and they're willing to do just about anything to settle their scores with the Duke. Lavish in its staging, full of passion and swordplay, and based on a true story, The King's Thief also features a young Roger Moore as Dermott's sidekick Jack, and the distinguished George Sanders (All About Eve) as the painted, bewigged King.