Shadow of a Doubt (1943)

Shadow of a Doubt (1943) is an early film noir era Alfred Hitchcock charming uncle  prototypical mainstreet serial killer psychopath philosophical murder mystery shocker oncle-noir suspense thriller drama, which is a also a classic film noir, and surely indicative of Hitchcock's effect on and contribution to the style.

It is noted in these chaumers that Alfred Hitchcock is a genre unto himself, and there is a lot of truth in that. So distinct becomes his work, from its earliest to its latest, and undoubtedly it is the same, and uses motifs and styles that only he seemed to be able to excel within. 

His to-camera photography is unique in that it never breaks the fourth wall, but looks through the fourth wall to place his target character within the mind of the audience. Compelling.