Beauty and the Beast: Part One

Merlin and Gaius suspect that Lady Catrina is not quite as she seems after she shows up in Camelot. Arthur isn't happy when his father flirts with her. When Merlin discovers that she is really a troll, he finds it impossible to get Arthur to listen to him. Merlin tries to stop Catrina from ruining Uther's life, but she has her eyes set on an even bigger prize.