Charlie Chan en Alcatraz

A bank is robbed, and a guard is shot to death. Clues lead the police to the Foss Family Hotel where we meet a varied group of unsavory suspects.

Thomas Harley, who resides at the hotel along with his beautiful daughter June, is the one that the police are after-- it was his fingerprints left on the safe that led the police to the hotel.

He claims that he was locked up in a theatrical warehouse, but he has no witnesses. Even more suspicious is his story that he had received a letter from a man he hadn't seen for many years, asking him to a meeting at the warehouse; but the prosecutor can prove that the man had been dead for eight years.

Chan thinks the set-up is much too pat, and he doesn't give up on Mr. Harley when Harley's daughter June makes an appeal to him to help free her innocent dad. But how can he account for those fingerprints?