In the fall of 1962, whilst The Birds was in post-production, François Truffaut carried out extensive interviews with Alfred Hitchcock at his offices at Universal Studios. The interviews were recorded to audio tape and the content eventually edited down into Truffaut's Hitchcock book.
Although Truffaut could speak a little English, he hired Helen Scott (of the French Film Office in New York) to act as the translator for the interviews.
Truffaut had intended to quickly publish the book of the interviews, but the first edition wasn't published until several years later (1966 in France and 1967 in America). To bring the book up-to-date, Truffaut conducted further interviews to discuss Marnie and Torn Curtain.
In 1984, Patricia Hitchcock donated a set of the interview tapes to the Margaret Herrick Library, where they are now part of the Hitchcock Collection. Although Truffaut claimed that the recordings lasted 50 hours, the surviving tapes — which cover the 1962 interviews — last for less than 26 hours.
Research by Janet Bergstrom has made clear the fact that the book often does not contain a verbatim transcript of Hitchcock's responses to Truffaut's questions.
The audio tapes of the interviews have not been released commercially. However, portions of the tapes were used for a French radio broadcast by the station "France Culture".
Nearly 12 hours of the interviews were broadcast on French radio as a 25 part series. Each episode runs for just over 25 minutes.
Transcriptions are available for some of the parts.
Childhood through to his early years in the film industry.
[Written summary taken directly from https://the.hitchcock.zone/wiki/Alfred_Hitchcock_and_Fran%C3%A7ois_Truffaut_(Aug/1962)]
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