One index of the richness of Hitchcock’s work is the wide variety of critical approaches it has inspired. For the late great Raymond Durgnat (The Strange Case of Alfred Hitchcock), the balanced perfection of The 39 Steps was unsatisfying: he contrasted its ‘dapper heroics’ with what he saw as the greater profundity of the thriller that followed it.

Set in Europe during the Great War, Secret Agent has a less positive and charismatic British-agent hero (John Gielgud), its moral issues are less clear-cut, and its train-crash ending caused problems that led to re-editing – all of which makes it more interesting rather than less, especially when juxtaposed with its predecessor, whichever of the two one prefers. The film should not be confused with its successor, based on Conrad’s novel The Secret Agent, retitled as Sabotage.

This film is screening as part of The Genius of Hitchcock: Part Three (February 2nd – 27th), which is part of a complete retrospective of the filmmaker’s work running until March 2013.