Gawain fights alone against the assassins Mortlach and his men who have come to the Demon World to eliminate the Four Horsemen of the Apocalypse. Meanwhile, Percival meets one of the assassins, Rosebank, and tries to talk to him. At the same time, Tristan, who is in the Demon World's castle, receives information from the Demon King Zeldris about a door leading to Camelot, but... (thetvdb.com)