Factual error: When William Holden visits the Special Operations HQ for the first time a black vehicle is seen pulling in to the complex. The car is a 1948 Dodge or other Chrysler product which had not yet been manufactured.
Factual error: The opening credits incorrectly list Alec's last name as "Guiness." It's "Guinness." [This is only in certain prints of the film. In other prints, his name is spelled correctly.]
Factual error: In the headquarter scenes, the Jeep's windshield wipers had a distinctive aftermarket electric motor, which was not available until after the war.
Factual error: There are many scenes where Japanese soldiers are using British weapons. Vickers machine guns, Enfield rifles, and Sten sub-guns.
Suggested correction: Captured stock taken on the fall of Singapore and the surrender of the British forces stationed there – and their weapons. They were allocated to POW camps which were considered unworthy of regular Japanese weaponry.