Frenzy actual London serial murder cases: the Christie murders in the early 1950s, and the Jack the Ripper murders in 1888. Barry Foster has said that, in order to prepare for his role, he was asked by Hitchcock to study two books about Neville Heath, an English serial killer who would often pass himself off as an officer in the RAF. "Frenzy" was the third and final film that Hitchcock made in Britain after he moved to Hollywood in 1939. The other two were "Under Capricorn" in 1949 and "Stage Fright" in 1950 (although there were some interior and exterior scenes
The Doctor (Doctor Who) footage. Tom Baker did reappear, but as "the Curator", an ambiguously different character who he was not credited for playing. A voice actor, John Guilor, recorded a line of audio impersonating the First Doctor, for which he was credited as "Voice Over Artist". In other multi-Doctor stories, the multiple actors are all credited as "The Doctor", the exception being "The Three Doctors" (1972–73), which credited William Hartnell, Patrick Troughton and Jon Pertwee as "Doctor Who" as the 1972 serial preceded the practice of crediting the character as "The Doctor". In "Human Nature" (2007), the plot involves the Tenth Doctor altering