The evil sorceress Nimueh (Michelle Ryan) is back to wreak havoc on Camelot. This time Merlin is her target, and she tricks the young warlock into drinking from a poisoned chalice, causing him to fall dangerously ill.

Arthur must venture to the caves deep beneath the forest of Balor to obtain the antidote, but he does not realise he is walking into a trap. Determined to thwart his quest, Nimueh does everything she can to stop him.

Can Arthur overcome these magical hurdles and make it back in time to save his friend?

The fantasy adventure romp based on the legend of King Arthur continues. When the Lady Morgana is struck down with a mysterious illness, Gaius is at a loss for a cure. Thankfully a new physician, Edwin Muirden, is on hand to bring the King's ward back from the brink.

As the stranger charms his way further into Camelot's court, winning over everyone from Uther to Merlin, Gaius begins to doubt his credentials. Just who is the mysterious newcomer and what does he want with the royal family? Gaius' loyalty and bravery are going to be tested to the limit if he is to find out.