An ambitious attempt to wed the legend of King Arthur and his Knights of the Round Table with known historical facts of the era, this action adventure drama begins with the fall of the Roman Empire in 450 A.D. as Roman armies flee the British Isles. Arthur (Clive Owen), a heroic knight and devoted Christian, is torn between his desire to travel to Rome to serve his faith and his loyalty to the land of his birth. As England falls into lawlessness, Arthur throws in his lot with a band of knights who hope to restore order to their fair and pleasant land and hopes to win freedom for his comrades, among them Lancelot (Ioan Gruffudd), Galahad (Hugh Dancy), Tristan (Mads Mikkelsen), Gawain (Joel Edgerton), Bors (Ray Winstone), and Dagonet (Ray Stevenson). In time, Arthur and his men join forces with Merlin (Stephen Dillane), a shaman whose band of renegade knights were often pitched in battle against Roman forces. Forming a united front as loyal Englishmen against the invading Saxon armies, Arthur, Merlin, and the brave and beautiful Guinevere (Keira Knightley) are determined to unite a sovereign Britain under one army and one king.