There are two musical interludes in San Quentin (1937). One of these finds Ann Sheridan on stage in a night club. Of the other - a rendition of “I'm Forever Blowing Bubbles” -, well, I shall not reveal any more except to say that here is another of those tremendous Warner Brothers movies so hard boiled that one relishes the shell cracking as these sixty-seven minutes move relentlessly to a tragic conclusion.
Ann Sheridan is sister of Bogart who, since adolescence, has fallen in with a bad lot and done time in Reformatory and gaol before landing back there for ten years. As chance has it, she finds that in her bar's audience is a man - Pat O'Brien - who becomes smitten by her just as he is about to be seconded from the Army to take charge of the gaol.
Which is quite a complication - all the more so as he is decent man who likes to see the best in all but the worst (the latter he reckons to be a distinct minority). Even so, he is up against the inmates' hierarchy, a pecking order way beyond the cage of any henhouse. Alongside many a hemmed-in scene (cell; office) there are several on a parade ground where a careless taunt can bring brawls - including one by a prisoner who has turned, vocally, to the Bible, and snaffles a gun to prove his point (blessed are the rifles, one might almost say).
Much of this is owed to a taut screenplay sharpened by another Humphrey: Humphrey Cobb. He died a few years later, and would gain wider recognition when Stanley Kubrick filmed a novel based on his Great War experience: Paths of Glory.