The phone number in the title belongs to an old scrubwoman. She is offering a $5,000 reward for information that could free her son, who is serving a life sentence for murder. P.J. McNeal (James Stewart) is the Chicago Times reporter who calls the number. What he wants is a story to sell papers; he doesn’t care about guilt or innocence. But he is drawn in by the compelling Frank Wiecek (Richard Conte), who swears he has been wrongly convicted of killing a police officer. McNeal starts scratching the veneer of the 11-year-old case and suddenly finds himself at odds with a hostile police department, his doubtful publisher, and an impatient D.A.’s office. The stories of his campaign to clear Wiecek are read by thousands every day, but in the campaign itself, McNeal is alone.

We have entered the genre known as DocuNoir, and Call Northside 777 may be its best example. Though included in Fox’s Film Noir series, it skirts many Noir conventions. It trades the moody menace of M or Double Indemnity for the detailed realism of a police procedural—the goal is to recreate the true story it’s based on. Documentary footage is matched to staged footage, a narrator opens and closes the action, and scenes linger on the technology of the era. It’s less gripping, plodding at times, but utterly authentic. How authentic? The actor who gives Wiecek the lie detector test is actually the inventor of the polygraph.

I learned that from the commentary by film historians James Ursini and Alain Silver. (A slow-paced movie is perfect for a commentary because the speakers don’t have to rush.) It serves two purposes: to give us the real-life version of events as they unfold on-screen, and to place this film in the Noir universe. Ursini and Silver know director Henry Hathaway’s work and identify his trademarks. Fox also includes the original trailer, ludicrously over-the-top, and a rather useless Movietone clip of the stars posing and waving during the premiere. It’s only worth watching to see Jimmy Stewart get his star on the Walk of Fame.

Northside was the first film to be shot in Chicago, and when I say "in Chicago," I mean in every office, tavern, back alley and records hall; in the Illinois State Penitentiary, in police stations, in Polish neighbourhoods. The entire character of the film is yoked to Chicago, and the high-contrast picture quality does it justice, with some holes and blemishes. The cover sleeve says that the full-frame format "preserves the aspect ratio of its original theatrical exhibition." Well…okay. But technically, in 1948 the aspect ratio would have been 1:37:1, so 1:33:1 isn’t precisely…ah, forget it.

The Dolby Digital sound can be played in mono or stereo, but your crackalackin’ Bose speakers won’t get a workout. There is an Alfred Newman score over the opening and closing credits which plays smoothly. Otherwise, only ambient sound is used. This eliminates the problem of uneven levels.