The Doctor instructs Ace to draw a chalk circle around herself to protect against Morgaine's sorcery. He then drives off in his old car, Bessie, hoping to halt a battle between Morgaine's knights and the UNIT soldiers. A storm breaks outside the hotel, so Ace and Shou Yuing draw the circle around themselves and Excalibur (which is the real source of their protection). Ace and Shou Yuing start to bicker, and Ace nearly leaves the circle before realising that Morgaine is toying with their minds.