Place of Origin:
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Forrest was a police officer from Bristol. In the 2010s, Clara Oswald, using the Twelfth Doctor’s psychic paper, introduced herself and Rigsy to Forrest as MI5 agents. Together, they investigated the house of a missing person, where Forrest received a call from her superior.
Answering it, she walked out to another room, where she was captured by the Boneless, who dissected her and placed her flattened nervous system on the wall. The Boneless later attempted to take on her form. (Flatline)