After defeating Morgan, Lancelot (Leo Suter), establishes himself as the greatest knight. At the same time Mark of Cornwall (Peter Capaldi) hires his nephew, Tristan (Jack Reynor) to kill The Marhault (Domhnall Gleeson) to free Mark from a debt owed to King Anguish of Ireland (Ciarán Hinds). Tristan then falls in love with Isode (Hayley Atwell), Anguish's daughter and Mark of Cornwall’s wife. When Mark learns of Tristan and Isode’s relationship, he exiles Mark from Wales. Because of his exile, Tristan can longer use his real name, he takes up the title of the Black Knight. As the Black Knight, he duels many of King Arthur’s knights. After one, he is captured and placed in jail. When he escaped he duels Lancelot and it ends in a drawl. After the duel the two become friends and Tristan joins King Arthur’s Round Table. Also at this time Galahad (Sam Claflin), finds Lancelot and revels that Lancelot is his father. Galahad is found to be worthy to sit in the Sege Perilous the seat at the Round Table that no knight has been worthy enough to fill. With all of the knights, a quest for the Holy Grail begins.
