In March 1935, several publications carried brief details about a planned film titled London Symphony, which would star actor Clive Brook and be directed by Hitchcock. The scenario was to be written by H.M Harwood and based on an original story by Sir Philip Gibbs and his son Anthony.
Given the date of the announcement, it seems likely this would have been Hitchcock's next project following the completion of The 39 Steps (1935). Instead, Secret Agent (1936) became the director's next film.
It seems likely the project was abandoned at an early stage, as no film with that title was released.