Five stars for this Ben Hecht-Charles Lederer-Henry Hathaway collaboration based on a story by Eleazar Lipsky. All-Stars Victor Mature, Richard Widmark, Karl Malden, Brian Donlevy in a documentary-style noir thriller about a stoolpigeon who gets it in the end--for a higher cause.
Leading lady Colleen Gray was good, too. Reminded me of "On the Waterfront"--only scarier.
You can rent it from Netflix.