Language is a code: to break the code, the man who knows the code must be broken.
In The Darkest Hour is a story of survival against the odds.
The story starts in late May 1940 in Northern France. As the German Army pushes the British Army back to the sea, two Scottish soldiers find themselves in a perilous situation. Hamish McNeill and his sergeant –Gordon McGregor– are the sole survivors of a ferocious fight with superior German forces; with the aid of a French family and secret, underground rooms, the two soldiers manage to evade certain death.
Hamish and McGregor concoct a plan to get back to their own lines. Putting off their uniforms and dog tags, the pair don working men's clothes and are shown a route to the sea. But the two buddies are at loggerheads from the outset! Hamish is bitterly resentful of McGregor's cowardly, self-serving attitude to their fallen comrades; for his part, McGregor despises Hamish's naive outlook. And it is not long before things boil over between them: in the climax to a rough-and-tumble struggle down a woodland hill, they land at the feet of a German patrol.
Face-to-face with the very danger they wanted to avoid, Hamish falls back on the only defense he has –his native Scots Gaelic. The Germans are confused and bamboozled by this strange tongue and fail to notice that McGregor has nothing to say. For McGregor has no Scots Gaelic and one word of English from him will be a death sentence. Out of uniform and with no identification cards, the pair will almost certainly face a firing squad.
Taken to a local interrogation centre, Hamish whispers to McGregor that the latter should play dumb so that Hamish can foil any awkward probing by dint of his incomprehensible Gaelic. This seems to be working until a Nazi agent (posing as a refugee) pretends friendship –only to stub a cigarette out on McGregor's hand. The resulting outburst (though not identifiable as English) confirms that McGregor can indeed speak. The thread that they hang by is getting steadily thinner.
The action moves to Berlin, right into the wolf's lair of a Nazi interrogation centre. Here the pair are confronted with the full terrors of Nazi methods. It is make or break time. If they are to get out alive, they have to find a way of working together. And Hamish has to find a way of getting through to McGregor, to make him understand that they are in the same boat, headed for the same rocks! This point is reached when McGregor witnesses the execution of a female prisoner in the yard below his cell window. For the first time, the self-centered cynic feels pity and remorse and a powerful force of change begins to work in him.
With Hamish teaching McGregor some few words of Gaelic, it seems to be enough to fool their captors. Until, that is, the Nazis dish out a brutal beating to McGregor. Under the onslaught he manages to avoid speaking any English. But McGregor's spirit is broken. Brought back from the brink by Hamish, the two Scotsmen open their hearts and minds to each other. This Dark Night of the Soul ends with a revelation to McGregor. In the wee hours, he wonders if they could pretend to be from beyond the Russian border.
Hamish points to Armenia when a map is produced and the pair are sent off to a border post where they will be handed over to the Russians. But they are not out of hot water yet. For a scratched graffito is almost their undoing: an intellectual Nazi captain sets out in pursuit of them –all the way to the border crossing. This sets up the final climactic scenes of the story. Will the Russians think they are German spies? Will they risk speaking English to the Russians? Will the Russians hand them back to the Germans? And will there be a final showdown between Russians and Germans over these dubious Armenians?