British army officer Brigadier George Grant gives a speech at the opening of his regiment's museum. He looks back to 1941 and imagines how things could have gone very differently:

Winston Churchill is killed in a German bombing raid. Grant, then a junior officer, joins his regiment. Britain makes peace with Germany. Some territories are shared, others taken by the Axis powers. Among the officers, there is only vague talk of resistance.

During the inactivity that follows the cease-fire, Grant becomes close to Kate, the wife of another officer. The regiment is provided with German weapons and instructors.

When a party of German officers is entertained in the mess, one directs a torrent of abuse at a Jewish British officer, and a tense toast is drunk to Hitler. By Christmas, the German soldiers are well established alongside the British regiment, though relations are not always cordial.

To the surprise of Grant and the regiment's other officers, several soldiers are re-posted to the Pioneers Corps in Dover. Those transferred are all Jews, including Kate's husband, who shoots himself. Grant and Kate become an item.

Grant attends an inquiry into the loss of a German machine-gun presided over by eccentric senior officer 'Nanny' Norris. It reaches no conclusions, and when Grant criticises Norris, it is pointed out to him that Norris has the lost weapon under his bed. Grant is informed that 'trustworthy' British battalions have been fielded against unarmed British civilians, and that his company will not allow itself to be similarly used.

Grant becomes friendly with a German officer, playing golf with him. He becomes acting company commander after Norris's deception is discovered. Grant is pleased when the news comes through that they are again at war, as Hitler has invaded Russia.

Promoted to acting adjutant, Grant marries Kate. On honeymoon in France, the couple encounter hostile opinion about Britain and learn of a channel tunnel being dug by Jewish slave labour, against whom they happily make casual anti-Semitic remarks. On their return to Dover, Grant witnesses a brutalised Jewish labour party. Among them is one of his former comrades.

Grant is posted to India, where he leads a company tasked with constructing a vast roadway up to the Eastern Front. While there he has to try, convict and execute a fellow officer accused of Communist treason.

Grant and Kate become estranged, both drinking heavily. Grant relents to the pressure applied by a Gestapo investigator and reveals compromising comments made by a previous company commander. This leaves him disturbed about the ethics of his actions in pursuit of his army career.

The German medical officer recognises Grant's fraught state and cajoles him into seeking solace in the local brothel. There, he breaks down in front of a prostitute. Suddenly, the camp is attacked by a force of Cossacks. Grant throws himself into the defence, but the camp is quickly overwhelmed. In a last self-destructive move, he orders an artillery bombardment of his position.

Many months later, Grant awakes in a German hospital. It is explained to him that his life was saved by advanced Nazi medical science. He now possesses new organs, limbs and an eye. The donors are the well-fed Soviet prisoners of war held outside the hospital. The longevity of Hitler himself has been secured by such means.

As a result of his actions, Grant is now a war hero and to be paraded throughout the Reich. He needs a wife, he is told, to complete the triumphant picture. He is reunited with Kate, who is horrified at what he has become.

Back in the conventional present, and in the present of the world in which we have followed his career, Grant completes his speech about why those gathered for the opening of the regimental museum are there. There is little to distinguish the two.

Note: Although much of it was recovered from the Granada Television archive, two fifths from the middle of the play remain missing.