Dial M for Murder (1954)

I used to consider this second-tier Hitchcock, but a re-watch proved to me just how excellent the script and directing were, as well as how stellar and underrated both Grace Kelly and Ray Milland tend to be, at least presently, three generations after the fact. The suspense is tied tighter than the proverbial drum. Needless to say, to this day, I never keep scissors on top of my desk anymore...