David Warner leads a band of modern day pirates who raid yachts and sail boats of people on vacation out in the Caribbean. Michael Caine is a reporter who goes out there with his son to investigate the mystery of the disappearing boats. He runs across Warner and his band of raiders and they decide to induct them into their tribe.

In the Eighteenth Century, in a small village in Ireland, Redmond Barry is a young farm boy in love of his cousin Nora Brady. When Nora engages to the British Captain John Quin, Barry challenges him for a duel of pistols. He wins and escapes to Dublin, but is robbed on the road. Without any other alternative, Barry joins the British Army to fight in the Seven Years War. He deserts and is forced to join the Prussian Army, saving the life of his captain and becoming his protégé and spy of the Irish gambler Chevalier de Balibari. He helps Chevalier and becomes his associate until he decides to marry the wealthy Lady Lyndon. They move to England and Barry, in his obsession of nobility, dilapidates her fortune and makes a dangerous and revengeful enemy.