The fantasy-drama based on the King Arthur legend (and dewy featured younglings) continues, as a deadly plague spreads through Camelot. When it seems that sorcery can be the only possible explanation, Merlin and Gaius race to find a cure, while Gwen is arrested and sentenced to death for practising witchcraft. Venturing deep beneath Camelot to unmask the true culprit, Merlin, Morgana and Arthur are faced with a terrifying beast, conjured by the evil sorceress Nimueh (played by the recently bionic Michelle Ryan). Can they expose the truth before Gwen is executed? And, more importantly, will any more pretty boys appear on the scene? Strictly Come Dancing follows at 6.45pm, and will see the remaining seven male celebrities dance either a jive or a tango to stay in the competition, while their female counterparts perform in a group dance. The results show is tomorrow at 8.10pm.