This is the second of three on-screen pairings of Linda Lin Di Ho (Ming Lu) and Richard Loo (Liu Yang). The first was in Vincent Price's historical adventure film Confessions of an Opium Eater (1962), which shared a similar plot point of Chinese women sold into slavery. The third and final time the two performers worked together was on Jeannie and the Kidnap Caper (1966), in which Ho and Loo played Red Chinese spies who abduct Major Tony Nelson.