During World War II (when this film was made) Anna May Wong went out of her way to clarify that she was of Chinese heritage and not Japanese. This included regularly supporting and doing volunteer work for organizations raising funds for Chinese resistance to the Japanese invasion and domination of China.
Blonde Mae Clarke who plays the singer sympathetic to the Chinese resistance's cause, had both of the best known roles in the same year. In 1931, she was featured as both the gun moll in whose face James Cagney mashed half a grapefruit in The Public Enemy (1931), and as the bride of Victor Frankenstein, who was terrorized by the monster in the original Frankenstein (1931).
During World War II, with the negative attitude toward Asians, accomplished Chinese-American Hollywood star Anna May Wong was reduced to making only two feature films, including this one, both for the poverty row PRC (Producers Releasing Corporation).
This was one of several war-era films in which Harold Huber was cast as an Asian, even though he was of Russian-Jewish descent.
It's in all likelihood a coincidence, but Ludwig Donath's character is named Hans Gruber, which 46 years later became famous as the name of Alan Rickman's villain in Die Hard (1988).