He Walked by Night (1948)
Narrator: And so the tedious quest went on. Sergeant Brennan wore out his shoes and his patience going from police station to police station, checking photos until his eyes were blurry. For police work is not all glamour and excitement and glory. There are days and days of routine, of tedious probing, of tireless searching. Fruitless days. Days when nothing goes right, when it seems as if no one could ever think his way through the maze of baffling trails a criminal leaves. But the answer to that is persistence and the hope that sooner or later something will turn up, some tiny lead that can grow into a warm trail and point to the cracking of a case.
Narrator: [referring to the composite sketch] They showed that picture to the inmates of jails and prisons, to men with a wide acquaintance among the cat burglars and the violence boys. Informers and con men and sharpshooters were quizzed. Those on the fringe of crime and those deep in the rackets. Many wanted to help; nobody could. No one in the underworld recognized that mysterious face. He was as unknown as if he had lived in the 16th Century.