In his pre-Charlie Chan days, Warner Oland returned as Dr. Fu Manchu for this sequel to The Mysterious Doctor Fu Manchu (1939). Supposedly the victim of a suicide at the end of the first film, Fu Manchu has actually injected himself with a toxin that will make him only appear dead. Escaping through a trap door in his coffin, Fu Manchu travels to England to seek revenge on the two men he holds responsible for the deaths of his wife and child: Dr. Jack Petrie (Neil Hamilton) and Inspector Nayland Smith (O.P. Heggie). A murderous game of cat and mouse ensues.
by Karl Williams synopsis