Charlie Chan in Shanghai

Charlie Chan in Shanghai is the ninth Charlie Chan film produced by Fox with the title character played by Warner Oland.

Charlie surprises everyone by arresting James Andrews. Lee Chan reveals that his father sent him off to cable America, and he has just received a reply which indicates that the real Agent Andrews was murdered in San Francisco three weeks earlier. The false James Andrews is really the leader of the Marloff gang, and intended to have the gang murder Charlie in a shootout when they descended through the trap door. Charlie knew Andrews did not really call the police, and had Lee summon them instead. Nashs escape from police custody was planned by Charlie. Charlie reveals that Forrest used the ink pad to put Nashs thumbprint on the revolver to frame him. Nash is declared innocent, and Andrews and Forrest go to jail.

Source: Wikipedia