Two young men, fleeing from carpetbagger justice in the 1870s, come upon a scary, bitter Frank Lovejoy. Is this guy really COLE YOUNGER, GUNFIGHTER, or just some other guy framed up on phony charges who has a skin of iron, and a heart of cornmush?
By the time 1958 rolled around, the B-Western had shuffled off to television, and had been replaced by the serious "adult western". This shuffling allowed serious actors approaching a career hiatus -- like Frank Lovejoy -- a chance to work for studios like Monogram (er, "Allied Artists") and retain some shred of reputation. This is good -- because Lovejoy, not a Western actor by any stretch, gives a good performance of the character called "Cole Younger" here. Younger, alas, is pretty much an old softie as portrayed here, and consistently puts his neck on the line for the young hero, in ways that are implausible for any historically accurate outlaw. But Lovejoy (who has a great voice for urban and gangster parts) brings some bite to the role, and at least projects a sense that this guy might have held up a stage or two, because mean people drove him to it.
The rest of the film is standard fare -- reminiscent of an episode of the "adult" TV westerns of the day (Not as good as Gunsmoke...more like Bonanza or the Big Valley). If you like westerns, you won't waste your life by watching this.