After a hiatus, star Sidney Toler brought Charlie Chan to Monogram Pictures in this wartime mystery. A inventor working on an advanced torpedo design is killed for the plans of his invention, though the exact means of the crime are unclear initially. Charlie is called upon to sift through a houseful of suspects, including a brusque refugee, a foreign trio who may be concealing secrets, a tight-lipped housekeeper, and more. Two younger members of the Chan clan, son Tommy (Benson Fong) and daughter Iris (Marianne Quon), meddle in the investigation, but the standout of the supporting cast is Mantan Moreland, an actor whose comedic stylings would prove a highlight of the Monogram Chan movies.

  Mildly recommended. Otto judiciously thinks this movie is worth a look, especially for fans of the series.