Undoubtedly the least-known, least-shown and least-respected film in this series, Number Seventeen is arguably the key transitional film in Hitchcock’s career. Forced by his producers to adapt, on a tiny budget, a comedy melodrama from the London stage, he approached it, by his own account, in a careless spirit, going headlong with the flow. The experience can be seen, in retrospect, as liberating, laying down the template for all the Hitchcock thrillers that were to follow. For the first time in his work, we get an overnight romance; a ‘Maguffin’ (the object of a search, which may be unimportant in itself but which structures the narrative, in this case a diamond necklace); and the sustained use of models (bus, train, boat, buildings) in a spectacular action climax. A curtain-raiser for the thriller series to come, and a rare pleasure in itself.