Forget the remake with Gene Hackman, the original The Narrow Margin (1952) is one of the top ten film noirs ever made, anywhere, anytime. And the greatest part of the film is aboard a train. Even better, for us FRNs. Charles McGraw can play it good or bad and in this film he is a cross between the two (maybe his best placement yet), and a cop. He's tough with everyone until he meets his match — one Marie Windsor.
Marie WindsorNo matter what great and dirty B-film she is in, including The Sniper or The Killing (just a few moments each), with a posse of roughnecks in either film, Marie Windsor takes over and owns it. One could almost say present day actress Illeana Douglas is her spit image (see the latter in the remake Cape Fear and To Die For ).
Back to the train. It's a Richard Fleischer film, without a doubt his best, and there's a slain gangster's widow to protect (enroute to a trial) with 2000 miles inbetween (Chicago~LA). Back when they used to know how to edge a film in black and white, all at a crisp 71 minutes. No fuss, no muss.