Remarkably, Hitchcock shot this adaptation of Frederick Knott's stage hit in 3D, just when the fad was on the wane (in 1954). The director himself said, "It was a nine-day wonder, and I came in on the ninth day." Now it has been carefully restored by the Warner Bros team, though its staginess remains impervious to tinkering.
The bits of business over latchkeys and phonecalls are at once mundane and complicated: the plot is worked out in the dogged manner of a mathematical problem. Its strengths are in the casting of Ray Milland as the suave ex-tennis pro who's mired in debt and thus determined to bump off his unfaithful wife (Grace Kelly, in her lovely prime).
And there's a wonderfully chilling moment when the fraudster (Anthony Dawson) Milland is blackmailing finally signals his collusion in the dirty deed by snatching up the cash. It's terribly dated, particularly about marriage: the success of the husband's scheme depends on the wife agreeing to stay at home to paste his old clippings in an album. Some men just don't deserve to have Grace Kelly as a wife.
This was the film Hitchcock made just prior to his great run of Rear Window, The Wrong Man, Vertigo and North by Northwest; you can almost hear his brain ticking over, waiting for the material that will come up to snuff.