Looking around at their new surroundings Donna noticed a sandy beach and water, "are we in Wales," she queried pointing to the castle on the hill. The Doctor came up behind her wrapping his arms around her, "does it matter where we are as long as we're together?" Smiling Donna leaned into his embrace kissing his cheek, "I love you, even if you are horrible at navigation," she retorted. "Hey now," he feigned hurt making Donna giggle. Sighing in his arms Donna felt something press into her, "Theta what's in your pocket," she asked. Standing up straight the Doctor reached into his jacket, pulling out a peculiar looking machine that began ringing as he produced it, "it's a machine that goes ding. Made it myself, lights up in the presence of shape-shifter DNA. Ooh! Also can microwave frozen dinners from up to 20 feet and download comics from the future. I never know when to stop," he explained. "So why is it dinging Theta? I'm certainly not an alien," Donna dared.
Expanding the antenna, the Doctor began running off to the other side of the clearing, seeing a lady on a horse. Following behind Donna tried to keep up, meeting him and ginger woman, "I do not understand," she heard the woman exclaim now dismounted from her horse. The Doctor shook his head, "You're a zygon," he declared. "A Zygon," the woman asked quizzically. The Doctor sighed, "a Zygon, yes. Big, red, rubbery thing covered in suckers," he explained. "Doctor," Donna interrupted. "Not now Donna," the Doctor dismissed her protest. The woman became flushed red, fisting her hands, "I certainly am not. I'm the Queen of England how dare you," she objected. Donna smacked his arm to get his attention, "Doctor," she urged. Turning to see what was wrong he noticed that where the horse once stood now stood a giant Zygon, "oh. It was the horse," he exclaimed.
Taking Donna's hand the Doctor began running, "what's going on," Elizabeth shouted as the Doctor grabbed her hand too leading them away from the Zygon and to safety. "We're being attacked by a shape-shifting alien from outer space formerly disguised as your horse," he explained. Elizabeth struggled to run and hold her massive dress, "but what does that mean," she shouted seeking further clarification. "It means you're going to need a new horse," Donna shot rolling her eyes and making the Doctor smirk at her come back.
Pushing them behind a rock archway the Doctor ducked behind also, "where's it going," Elizabeth asked. The Doctor turned to Donna, "I'll hold it off, you run. Go with Elizabeth," he ordered. "If you think I'm leaving you alone," Donna began to protest but the Doctor stopped her, placing his finger on her lips. "Her people need her," he supplied pressing a kiss to her lips.
Running in the opposite direction of the Doctor, Elizabeth and Donna ran into the forest, "the castle is this way," Elizabeth encouraged still struggling with her dress. Hearing footsteps behind them Donna gasped turning to see what it was and meeting face to face with a Zygon, "Doctor," she screamed before passing out.