01E04 - Lady of the Lake

Whilst Guinevere wants to leave Camelot with Leontes he is obliged to stay as one of Arthur's knights being trained by Gawain, a brilliant strategist, who breaks Arthur's sword in combat. Having warned Arthur to resist his feelings for Guinevere Merlin sets out to have a new sword made by reclusive bladesmith Caliburn, a widower living with his daughter Excalibur. Caliburn's desire to give Arthur the sword he has fashioned himself leads to Merlin's destroying him with magic and, inadvertently drowning Excalibur, after whom he names the sword. Morgan, meanwhile, is struck down by a mysterious sickness and healed by Sybil, a nun who was once her teacher and knows all her secrets.