Don't Mess With a Knight: In the 13th and 14th centuries, the influence and power of some key Norman knights, in particular William Marshall, helped alter the landscape of Ireland. Featured castles in this episode include Luttrellstown, with exclusive access to the location where David and Victoria Beckham got married; Kilkenny, once the capital of Ireland; the majestic ruins of Dunamase; and the famed Blarney Castle.