Uther lusts after Cornwall's wife, Igrayne (Katrine Boorman). He commands Merlin to cast a spell that will allow him to spend the night with her. Merlin agrees on the condition he can seize any child from their extramarital union. Cornwall is killed, Igrayne conceives, Uther is killed, and two decades later their son Arthur (Nigel Terry) is acclaimed king, as the only man who can extract Excalibur from the stone.
King Arthur forms the Knights of the Round table. Thanks to Excalibur's powers, Arthur is able to better Lancelot (Nicholas Clay). Lancelot becomes Arthur's foremost knight. The kingdom's tranquility is disturbed, though, by the sorceress Morgana (Helen Mirren). Morgana is Arthur's older half sister, the daughter of Uther and Igrayne. Morgana tricks Arthur into believing she is his wife Guenevere (Cheri Lunghi), and Morgana is impregnated.
Morgana arranges an affair between Guenevere and Lancelot. They are discovered by Arthur. Guenevere becomes a nun, and Lancelot flees to become a mad prophet. Morgana conceives Arthur's bastard inbred son, Mordred (Robert Addie). Arthur falls ill, and lingers near death for many years. His health can only be recovered by the Holy Grail. He commands his knights to search for it.
Mordred grows up into a malevolent warrior who demand's Arthur's title of king. Sir Perceval (Paul Geoffrey) somehow finds the Holy Grail, and Arthur is restored. Arthur and Mordred's respective forces gather for battle. Merlin re-emerges to aid Arthur in his final battle.
Future A-list actor Liam Neeson has a minor role. Future "Star Trek" captain Patrick Stewart also shows up, as a knight unable to extract Excalibur from the stone. Three of Boorman's children appear in the movie, as Igrayne, young Mordred, and the Lady of the Lake.
How others will see it. Excalibur opened as #1 in the American box office. It became a moderate commercial success. The movie did garner one nomination each at the Oscars and BAFTA, but did best at the Saturn Awards, where it won for its costumes and had five other nominations, including Best Fantasy Film, Best Director, and Best Supporting Actor and Actress (wizards Nicol Williamson and Helen Mirren).
Today at imdb.com, the movie has a respectable 54K user votes. The user ratings climb with advancing age of the viewer, and range from 6.8 among women under 30, to 7.8 among women over 45. As one might expect from the user ratings, the user reviews are mostly positive ("the best of the King Arthur films", "the quintessential King Arthur movie!"). There are also the expected number of naysayers, one of whom quotes Shakespeare ("full of sound and fury, signifying nothing").
How I felt about it. Director John Boorman first drew attention with the Lee Marvin crime drama Point Blank (1967). Deliverance was acclaimed as a masterpiece, and placed him in the top rank of directors. His fall from grace came with the poorly received Excorcist II. Excalibur was his very next film, and at least partially redeemed his career.
The most obvious problem with Excalibur is that it covers three generations of the Arthurian legend, too much for a feature-length film. For example, the quest for the Holy Grail is encapsulated into a few scenes. We also wonder about the Merlin-Morgana relationship. Wouldn't he have recognized her evil nature before she became sufficiently powerful to ruin all his plans?
Of course, it is enjoyable to see future moviestars Mirren, Neeson, Stewart, and Byrne. The film is a visual treat, and Boorman does not shy away from the darker, grisly aspects of the Arthurian legend. Then again, Deliverance is something of a horror movie, and Excorcist II certainly was.