It would be surely every lawyer’s dream: to put Adolph Hitler in the dock.

Hans Litten achieved just that. In 1931, as the Nazi leader’s SA Brown Shirts ran amok in Berlin, the 29-year-old, half-Jewish lawyer humiliated the soon-to-be Fuhrer, called as a witness in the trail of four fascist goons.

His actions that day would see Litten endure the nightmare of arrest, torture and concentration camp incarceration.

He had one hope. His mother, well placed in German society even after the Nazis came to power, was prepared to make any sacrifice, suffer any humiliation, abandon almost any principle to see her son freed.

In the end it is Irmgard Litten’s slow realisation that her love for her child vanquished her own beliefs, and Litten’s own realisation he cannot compromise his, that are central to this new play by Mark Hayhurst.

Penelope Wilton (Isobel Crawley in Downton Abbey) plays Irmgard. In a powerful performance, Wilton’s quiet, determined, never overly-emotional mother quickly realises she must compromise with the newly-installed Nazi tyranny if her son is ever to survive.

As Litten is moved from one camp to another, she more than her son comes to understand that he is ultimately doomed.

During their one and only scene together, staged at Dachau Concentration Camp in 1938, it is the silence that speaks more of the waiting horror than their final words. Wilton’s standing ovation for her performance was richly deserved.

Martin Hutson plays Hans Litten. His is not bravey, he keeps insisting to his fellow political prisoners.

At the start of his ordeal his is a mixture of bravado and weakness. But as friends are liquidated his resistant inner core proves stronger than those who cage him and ultimately even his formidable mother.

A strong supporting cast, including John Light as Gestapo officer Dr Conrad, David Yelland as Lord Lifford Allen and Allan Corduner as Fritz Litten, make this a tremendous piece.

Director Jonathan Church extracts every inch of sinister from Robert Jones bleak set; Tim Mitchell’s use of lighting is superb.

Taken At Midnight reveals the human spirit at its most challenged and yet unbeaten.

Those who played these roles for real had no idea that one day their stories of valour could ever be told, the Nazi tyranny would pass. Knowing this makes their actions even more heroic.

Taken At Midnight runs until October 25.