The movie is loosely based on the French bond scandal involving Serge Alexandre Stavisky. After the fraud was discovered he either committed suicide or was murdered by the French police.
The large biplane that Nicole and Stefan fly from London to Geneva midway through the film is a Handley Page H.P.45, one of only four built, each of which had a unique name. The one in this film is "Horatius" as its registration, G-AAXD, can clearly be seen in the scenes of the aircraft taking off and landing. It was destroyed on November 7, 1939 as it was making an emergency landing on a golf course after returning from France on a transport mission.
Unfortunately there are no surviving examples of this plane as all four that were built had been destroyed by 1940.
Unfortunately there are no surviving examples of this plane as all four that were built had been destroyed by 1940.
Credit error: Egon Brecher is billed as Deputy Bergery, but in the film he's known as Deputy Duvalais.
The 300 French francs to attend the charity event for the children's hospital was the same as $18.34 at the time, which is the equivalent of about $363 in 2021.
Claude Rains was almost three inches shorter than Kay Francis. This difference was handled in a number of ways - camera angles, shot set-ups, lifts in his shoes, etc. However, there are a few scenes where this difference was not taken into account or dealt with successfully.