Starring: Robert Mitchum, Jan-Michael Vincent, John Houseman, Ali MacGraw
Factual error: The batman at the RAF station introduces himself as "Aircraftsman Horton" (which also appears on the credits). While a common mistake made by those outside the RAF, the rank is actually Aircraftman, without an "s".
Factual error: When Pug first arrives in London, a car can be seen driving on the right.
Continuity mistake: Part 3: Hitler enters the study and stands near the door with his hands clasped behind his back. The angle reverses, and his hands move instantly to his sides. Reverse again, and he's returned to his original stance. (00:20:00)
Trivia: Logan Ramsey, who played Senator Ike Lacouture, was the son of the radio operator who sent out the very first alert of the attack on Pearl Harbor on December 7th, 1941. Logan Ramsey Sr.'s famous message was, "Air raid, Pearl Harbor. This is no drill!"