Boorman cast Nicol Williamson and Helen Mirren opposite each other as Merlin and Morgana, knowing that the two were on less than friendly terms due to personal issues that arose during a production of Macbeth seven years earlier. Boorman verified this on the Excalibur DVD commentary, saying he felt that the tension on the set would come through in the actors' performances. Even though he was 35 years old, Nigel Terry plays King Arthur from his teenage years to his ending as an aged monarch. Several members of the Boorman family appear in the cast: his daughter Katrine played Igraine, Arthur's mother, and his son Charley portrayed Mordred as a boy. Because of the number of Boormans involved with the film, it is sometimes called "The Boorman Family Project". Costumes Bob Ringwood designed the costumes, with armor designed by Terry English. Filming Excalibur was filmed on-location in County Wicklow, County Tipperary, and County Kerry, with the interiors shot at Ardmore Studios. The early critical battle scene around a castle, in which Arthur is made a knight by Uryens while kneeling in a moat, was filmed in Cahir Castle, in Cahir County Tipperary, the Republic of Ireland, a well-preserved Irish castle. The castle's moat is the River Suir which flows around it. The fight with Lancelot was filmed at Powerscourt Estate's waterfall. Other locations included Wicklow Head as the backdrop to the battle over Tintagel, the Kerry coast as the place from which Arthur sails to Avalon, and a place called Childers Wood near Roundwood, County Wicklow, where Arthur comes on Excalibur in the stone. At the time, John Boorman was living just a few miles down the road, at Annamoe. According to Boorman, the love scene between Lancelot and Guenevere in the forest was filmed on a very cold night, but Nicholas Clay and Cherie Lunghi performed the scene nude anyway. Editing According to Boorman, the film was originally three hours long; among the scenes that were deleted from the finished film, but featured in one of the promotional trailers, was a sequence where Lancelot rescued Guenevere from a forest bandit. Adaptation Rospo Pallenberg and John Boorman wrote the screenplay, which is primarily an adaptation of Malory's Morte d'Arthur (1469–70) recasting the Arthurian legends as an allegory of the cycle of birth, life, decay, and restoration, by stripping the text of decorative or insignificant details. The resulting film is reminiscent