The Green Pearl (1930) is the second adventure in the Dr. Night trilogy by Aidan De Brune, (1874-1946).
This second story is gaudy crime yarns, which steadily veers into fantasy by the end (gravity powered aircraft without engines...) and features a very unlikely Asian villain who is as different from Fu Manchu as you can imagine: a small, colorless man of uncertain central Asian origin whose principal obsession is raising money by any means possible (invariably criminal) to recreate a long-dead central Asian kingdom of which his distant ancestors were kings. Most of the stories take place in and around Sydney, although the earliest known is set in Perth Western Australia and one of the novelettes in north Queenslan.
