Monster (The Colour of Monsters)
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An alien, calling himself a monster, had crashed on Earth. Injured, he made his way to a barn. He met a girl named Amy and convinced her not to tell anyone about him. He listened with contempt to her stories of her life, and when she got too close to him, he began to strangle her. He was stopped by the Doctor, whom he recognised. The Doctor gave him a chance to surrender, but he refused and was destroyed by the Doctor. (PROSE: The Colour of Monsters)