Mr. Wong in Chinatown is a 1939 American mystery film directed by William Nigh and starring Boris Karloff as Mr.

As with some of his previous investigations, Wong is given important information by the leader of a powerful tong (Chinese secret society).

The tong leader tells Wong that the princess had come to the United States with almost $1-million to arrange the secret purchase of airplanes that were to be smuggled into China.

As Wong continues the investigation he learns that all the money that the princess deposited in a local bank has been paid out—and that the signature on most of the checks is a forgery.

Wong becomes the target of a killer, and is aided in his investigation by a blonde, beautiful and energetic newspaper reporter.