After a long series of clips from his films in which victims were dispatched to eternity in almost every conceivable manner, the great Alfred Hitchcock stood up at a 1974 Lincoln Center tribute and said, "I still think the scissors is the best way."

He was referring to the scissors stabbing in "Dial M for Murder," a minor Hitchcock thriller elevated from the second-rate by the third dimension. The picture was shot and briefly released in 3-D during the fleeting heyday of the process in 1954, but the 3-D version was soon withdrawn and the picture existed in a mere two dimensions for the next 25 years.

Then some enterprising film buffs talked Warner Bros. into stitching together new 3-D prints of the film, a project that became time-consuming and costly, partly because of the extreme evanescence of WarnerColor, which goes all purplish in about three years. "Dial M for Murder" has opened at the Key Theatre for its first 3-D engagement in Washington in a quarter century -- or maybe ever -- and it's the kind of fascinating novelty no true lover of Hitchcock or of fascinating novelties would want to miss.

While other and lesser directors employed 3-D mainly to pelt audiences with attics full of hurled bric-a-brac, Hitchcock dared to use it on a story that takes place almost entirely within a few small rooms. Rather than open up Frederick Knott's stage hit about a man's meticulous murder plot against his rich wife, Hitchcock emphasizes and exploits the sense of claustrophobia, of characters being trapped by walls as well as by circumstances.

No commercial filmmaker ever used 3-D more deliberately, subtly or artfully. The picture becomes a study in spatial relationships, a visual mood piece and a ballet for furniture, particularly one big table lamp which often seems oddly prominent in Hitchcock's illusory domestic landscape.

Of course the real mysteries of "Dial M" are not obviated by the added depth; chiefly, how is it that Grace Kelly would ever marry a stiff like Ray Milland and then, to make matters more preposterous, be having a thing on the side with Robert Cummings? That's going from the bun warmer into the chafing dish. If anyone were going to commit murder, you'd think it would be the provocatively icy, regal Kelly, saddled with this colossal bore of a hubby and an even more insipid lover boy.

Hitchcock sets up the caper with a civility that is only an inch from self-parody; only Hitchcock could orchestrate this kind of gleeful austerity. Milland has invited over an old school chum now down on his luck (the effectively seedy Anthony Dawson) and lays out for him a morbid scheme whereby the buddy will hide one night in the couple's London apartment and, at the cue of a ringing phone, strangle the wife to death.

The plot goes momentarily awry when the wife, awakened by the call, foils the intruder and, in the most striking 3-D shot, reaches out toward the audience for help, finding Hitchcock's cissors instead. Dawson does a tremendous stylized stagger with the cissors in his back (thunderously abetted by composer Dimitri Tiomkin) and then, in the most sensational Hitchcock murder until Janet Leigh stepped into the shower, falls backward, driving the scissors in deeper when he hits the floor.

Even in 2-D, the scene is a breathtaker.

The second half of the movie is brightened by the arrival on the scene of a wily chief inspector played by John Williams, the very actor now making himself unwelcome in those endlessly repeated TV commercials for beloved melodies from the classics. Williams polishes off the case in the same droll manner as Alec McCowen in Hitchcock's "Frenzy" 18 years later, but not before a disruptively tacky courtroom montage in which the face of Kelly reacts to unseen lawyers and jurors who send her off to jail.

Even Hitchcock tended to dismiss "Dial M" as something of a doodle, but when the genius of his geometric approach was combined with the hallucinatory qualities of 3-D, the result was a kind of wry, animated Magritte. The lighting effects and insinuating camera angles enable Hitchcock to turn a small London flat into a virtual Grand Canyon.

Yes, you still need glasses for 3-D movies, though they are not as uncomfortable or as hard to keep on as they used to be. And if "Dial M," like all 3-D movies, doesn't lack for eye strain, it is devoid of the kind of eyepopping gimmicks people may expect, so the Key is teaming it with a properly ridiculous Three Stooges short, "Spooks," in which axes, knives and cleavers, most gliding on visible wires, are propelled into the house.

The Three Stooges in 3-D amounts to one D per Stooge. The mayhem is more ghastly than uproarious, but it's impossible not to be moved with a hatchet in your lap.