As Mrs. Salad pointed out a couple times: not based on the book by Shel Silverstein. And the title has, as far as I could tell, nothing to do with the actual movie content. Nothing of import happened at ended sidewalks. For that matter, I'm pretty sure no sidewalks were shown to be ending. Refund!
The movie stars Dana Andrews and Gene Tierney, just like Laura. And it was produced and directed by Otto Preminger, just like Laura. And it's… well, just OK, not as good as Laura. But still a fine example of the way they used to make 'em.
Andrews plays police detective Matt Dixon, who's gotten a bad reputation in the department as a loose cannon, the kind of a guy who punches first, and asks questions later, and also punches while asking the questions, and punches afterwards too. One sad evening, while investigating the killing of a Texas gambler knifed in a floating mobster-run crap game, he punches the wrong guy in the wrong way, and the guy ends up dead.
The plot is appealingly twisty: Dixon tries to cover up the death, hopefully framing the mobster responsible for the original murder. But—drat—some "clever" police work soon settles on a different suspect: the colorful Jiggs Taylor, father-in-law of the victim. But by this time, Dixon has fallen hard for the victim's ex-wife (Gene Tierney, of course); he'd prefer not to be responsible for framing her innocent dad. What a predicament!
Karl Malden has a supporting role as Dixon's by-the-book superior. I kept waiting for him to call Dixon "buddy boy", but he never did.