The Man Who Knew Too Much (1934) - Hitchcock's cameo
Hitchcock's cameo appearance in The Man Who Knew Too Much (1934) occurs approximately 34 minutes into the film.
As a bus passes by, two men walk from screen right to left. The bus has an advert for the "Isle of Man" — the location used in The Manxman (1929).
Given that the director made his next cameo appearance in The 39 Steps with screenwriter Charles Bennett, it is possible that Bennett is the man accompanying Hitchcock.
Hitchcock also made bus related cameo appearances in the following films:
- Number Seventeen (1932) — unconfirmed
- The 39 Steps (1935)
- To Catch a Thief (1955)
- North by Northwest (1959)
Hitchcock's face is only visible for a few frames of film...