Continuity mistake: When bringing the cannister up, the rope is rigged such that the lifting rope is under the supporting rope. But as soon as it appears on deck, the lifting rope has switched and is now over the supporting rope, and the tackle is nowhere to be seen. (00:49:00)
Factual error: Towards the middle of the movie when when the British submarine leaves port with the Man Who Never Was onboard, it is flying what appears to be an American flag. The flag is visible for about ten seconds and if you look closely, you can see the field of blue of the stars and stripes in the upper corner.
Suggested correction: The flag, as can be seen before submarine sails and then from a distance, is obviously the White Ensign.
Factual error: The movie is supposed to be staged in 1942. Early in the movie there's a date calendar on the wall behind 2 characters talking which shows "Friday April 12" There was no Friday, April 12 in 1942.
