Goofs

While searching for Thorndike at the bottom of the cliff, Major Quive Smith finds his shoe, yet in the first sight of Thorndike regaining consciousness in the brush, he is fully shod.

Capt Thorndike has a rucksack on his back with a strap across his chest, which is then found suspended from a tree branch. He would't have had time to undo the straps, let alone take it off.

When Quine-Smith has Thorndike trapped, he has his monocle in his right eye the whole time until the camera shot looking at him through the cave vent hole.

Quine-Smith tells Thorndike that Germany has just marched into Poland then a little later, while Thorndike, who only has a shoulder wound, is lying unconscious after being operated on, there are shots of war action and a newspaper placards announcing London and Coventry being bombed.

As Thorndike is being chased through London, the pub in the background has bat-wing doors of the sort found in Western saloons in the US. No pub in Great Britain has such doors; they have proper doorways that keep out the rain, fog and snow.

London tube trains have a unique four-rail electrification scheme---a third rail in the usual outside position at 420 volts and an unusual center rail at -210 volts. The movie's tunnel set has only the center rail.

From the top of a high cliff Quive-Smith throws Thondike's rifle over the top and after a moment or so it's heard to clatter as if on rocks and then a plop. When it's found it's sticking up muzzle down in mud but there's no rocks any where near.

The chess board is incorrectly set up. When facing the board, the lower right square must be the light color.

On the cast list, George Sanders is listed as Major Quive-Smith. The rank on his uniform indicates he is either an Oberst (Colonel) if the lapel rank is silver and the shoulder pips are gold; or he is a General if the lapel rank is gold and the shoulder pips are silver. It's impossible to tell with a black and white movie. The Luftwaffe ceremonial dagger he wears was worn by both ranks in the white tunic uniform. In either case he was not a Major.

In London, Jones is sitting on the edge of a fountain keeping a look out for Thorndike, whom he sees getting out of a taxi which despite being a left-hand drive foreign-make has a GB plate on. As the camera goes back to Jones, at least two big American cars go past.

After arriving at Lord Risborough's home, Jerry Stokes is able to perfectly recall his butler Reeves' surname, but not Alan's forename, despite it being mentioned several times and her evident interest in him.