Orczy's The Emperor's Candlesticks (1937).

Baroness Orczy,
from the July 1908
Brooklyn Daily
Eagle

Baroness Emmuska Orczy was born today in Hungary in 1865. In The Emperor's Candlesticks, based on the Orczy novel of the same name, William Powell and Luise Rainier are rival agents using candlesticks to convey secret messages. Robert Young and Maureen O'Sullivan costar.