Batman Detective #39

Detective Comics #39, published by DC in May 1940, features "The Horde of the Green Dragon!" Batman and Robin investigate kidnappings and an opium ring in Chinatown. The story is notable for the death of Batman's ally, Wong, and Batman's brutal methods against the Green Dragon gang. This issue is also significant for being Robin's third appearance and includes a full-page advertisement for Batman #1. The final panel teases the return of Clayface in the next issue.