...New York! This film is presented as a quasi-documentary (it is not). Though the story is fictional, the setting is entirely real - 1948 New York City. And that is the biggest appeal of the picture (I was born and raised there so I may be biased). Some interior shots appear to have been filmed on a sound stage, but the bulk of it is on location. For example, there is a scene filmed in lower Manhattan near Rivington and Norfolk streets. It show's a bustling, thriving "family" neighborhood with well dressed folks and kids playing in the neighborhood. It looks nothing like that now - just a place to pass through to get to somewhere else (though there is a school there now - check google maps and find the intersection - you can see the same building in the opening shot for that scene).
Story-wise, it's a pretty solid film especially considering how dated movies from this period can be. There appears to be a real attempt to make the movie as accurate as possible and goes out of its way to include the methods used in solving modern crimes such as forensics - probably a novelty at the time. The acting is solid throughout. I'm not sure how comfortable I am with the idea of a narrator - on the one hand, it lends authenticity to the documentary feel, but on the other, it can take you "out" of the picture at times. Overall, very worth watching. I give it a thumbs up (can I do that here?)
