Anachronisms: Some modern bulbs in close-ups of Enigma machines.
Anachronisms: In the opening scene we see concrete sleepers on the railway line which were not introduced until early 1980s.
Anachronisms: The black chimneys of Portcullis House, built in the late 1990s, can be seen in the long shots of the Houses of Parliament.
Anachronisms: Early in the movie someone uses the word "presently" to mean "at present" or "now". In the 1940s (and earlier) in England "presently" meant "soon, in a short time".
Anachronisms: Rape, though its bright yellow color makes for an attractive shot, was not planted in great quantities in England until the late 1970s.
Anachronisms: In the final scene, in London after the war (1946), Hester steps off the pavement and we see double yellow lines painted at the kerbside (denoting No Parking). These road markings were introduced much later.
Continuity: During the train journey towards the end of the movie, the view from Jericho's compartment shows the train going in opposite directions before and after the stop at the station, despite the fact that the train is seen leaving the station in the same direction as it arrived.
Anachronisms: Although set during the Second World War, all the scenes in and around Trafalgar Square show modern London buses in the background.
Factual errors: In the opening scene in London, a UPS van can be seen, clearly not a 1945 UPS van but a nice new modern one.
Factual errors: When Admiral Trowbridge storms off to his car after tearing strips off Skynner, Logie and Jericho he gives a British army salute (palm facing the person being saluted) and not a British naval one (palm parallel to the ground) before entering his car.
Anachronisms: The railway coaches seen in the film are British Railways Mk1 stock, which were not introduced until 1951.
Anachronisms: Some of the car scenes take place amongst fields that are clearly modern monoculture with huge tractor sprayer lines in the fields of grain.
Anachronisms: When Hester and Tom Jericho are sat in the car in the barn kissing, the light reflected off Hester's glasses, show them to be modern coated lenses. Coated lenses would not have been around during the 1940's.
Factual errors: Near the end of the film, when the submarine explodes, our hero is nearby in the water. Unfortunately, water transmits waves exceptionally well. Anyone in the water for at least a square mile would be immediately killed from the shock.
Factual errors: U-boats did not have a "klaxon" diving alarm.
Continuity: When Hester takes the enigma machine out of the car and into her flat she does not take the box with the battery. The battery is not seen in subsequent shots. The battery was needed to use the machine.