Fat Kim

 was a gangster in the 1950s. According to Norton Folgate, she was the largest gangster in Soho in both senses of the word. She came after Norton and Andy Davidson. Norton was apparently selling her alien guns. She also had artefacts which would be unlocked by the key in Andy's head. She wanted to take the key from Andy and when she did her head exploded. (AUDIO: Goodbye Piccadilly)