Cowardly rogue Harry Flashman's (Malcolm McDowell) schemes to gain entry to the royal circles of 19th-century Europe go nowhere until he meets a pair of devious nobles with their own agenda. At their urging, Flashman agrees to re-create himself as a bogus Prussian nobleman to woo a beautiful duchess. But the half-baked plan quickly comes unraveled, and he's soon on the run from several new enemies who are all calling for the rapscallion's head.

Tom Canty is a poor English boy who bears a remarkable resemblance to Edward, Prince of Wales and son of King Henry VIII. The two boys meet and decide to play a joke on the court by dressing in each other's clothes, but the plan goes awry when they're separated and each must live the other's life.

It's 1649: Mazarin hires the impoverished D'Artagnan to find the other musketeers: Cromwell has overthrown the English king, so Mazarin fears revolt, particularly from the popular Beaufort. Porthos, bored with riches and wanting a title, signs on, but Aramis, an abbé, and Athos, a brawler raising an intellectual son, assist Beaufort in secret. When they fail to halt Beaufort's escape from prison, the musketeers are expendable, and Mazarin sends them to London to rescue Charles I. They are also pursued by Justine, the avenging daughter of Milady de Winter, their enemy 20 years ago. They must escape England, avoid Justine, serve the Queen, and secure Beauford's political reforms.