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Fiona Bellows was a wheelchair user and a grandmother. While waiting for Christmas dinner, she fell asleep and was then attacked by a dream crab. In her dream state, she thought she was a scientist and a professor at the North Pole on Christmas Eve and had use of her legs. She was able to wake up from the crab-induced dream, killing the alien creature in the process, with the help of the Twelfth Doctor and Santa Claus.