Psycho Morph
From Tardis Wiki, the free Doctor Who reference
Vienna Salvatori once described a Psycho Morph as "a shape-changer with psychotic tendencies".
Psycho Morphs were beings that would murder high-profile or strong people and take their forms. They would mutiliate the bodies beyond recognition so that they could successfully steal the identity of the person that they had just mudered and blend into society.
One such Psycho Morph took the role of Doran Curtis, the chief of Crime Corps. Vienna lured the creature into a Personality Hotel, in order to wipe its memory and prevent it from committing more murders. This would buy her more time to solve the problem. (AUDIO: Tabula Rasa)