Gaffes

Near the beginning of the film, immediately after the reception of the diplomats, there is a scene of the German diplomat's vehicle leaving the reception. While the film takes place during WWII, the car is clearly passed by two early 50s American cars.

Foam in the Countess' beer while she talks with Count von Papen.

In the Argentinian passports it says: "Numera del Retratio", "FOT TOMADO ET PULGER DERECHO". Should be: "Número del retrato", "FOTOGRAFÍA Y PULGAR DERECHO"

The 1944 set film depicts a single - deck trolleybus system operating in Ankara [ seen behind Michael Rennie in one scene ]. Trolleybuses were only introduced to Turkey in 1947.

When the British ambassador's valet Diello (James Mason) suggests that his new German spymaster change the combination on the latter's safe, he gives the existing combination 1-30-33 as based on the date of Hitler's rise to power, suggesting instead 6-18-15, the date of the Battle of Waterloo. One would expect an employee of the Britsh Embassy (particularly one born in the UK) to have used "European" notation (date/month/year) instead of US notation (month/day/year), particularly when speaking with a German.

In one of the final scenes Diello is counting banknotes by quickly shuffling through them and all the while talking animatedly.