Paige accidentally summons a medieval knight, who believes Paige is the love of his life. However, the knight is under the influence of an evil sorceress.

When Piper and Leo begin to have marital problems, Piper casts a spell to allow them to literally see their past together. However, the spell goes awry when Phoebe and Paige are sent back in time to relive Piper's memories, and a warlock bent on destroying the Charmed Ones tags along for the ride.

The Charmed Ones are called upon by The Lady of the Lake to help protect Excalibur, the legendary Sword in the Stone. Meanwhile, numerous magical beings arrive at the manor to try their hand at pulling the sword from the stone, but it's Piper who finally pulls Excalibur out of the stone, causing a surprise figure to appear.