A philosophical debate may not be your idea of the most riveting drama, even when the subject is whether God has broken his covenant with the Jews. But Frank Cottrell Boyce's script was almost god-like in its ability to breathe life into such a potentially dusty subject and an ensemble cast of outstanding actors took his words and turned them into one of the most involving dramas to take place (almost) in a single room since 12 Angry Men.

The drama opened as a bus-load of tourists arrived at Auschwitz and were shown around by a young blonde tour guide. She explained that up to a thousand men or women would be housed in each cell and asked if they could imagine what that was like.

And then, the television fairy waved her wand and unlike those tourists we didn't need to imagine it. We were there, along with the men, as they sat around in their grubby prisoners uniforms and then marched across the frozen mud to be "selected."

It was not the job of this drama to examine the effects of such privation on the men who undergo it - many lines have been written on that already - and yet it cleverly worked in a pastiche of different attitudes and reactions in the first ten minutes. Some men take the spurious authority that is handed to them. Take their chance - perhaps the only chance they will ever have - to lord it over their fellows. Some conceal their fear with arrogance and bullying behaviour. Some pray. Some try to help others. Some give up and sit shivering, waiting for death.

Watching those first few minutes I thought again, as I always do when confronted with the terrible reality of those camps, that we should all thank whatever we hold sacred that we will never be told to run naked through some freezing shithole and then arbitrarily shoved Left or Right and not know which means death.

Faced with such treatment, is it any wonder a group of prisoners wonder whether their faith has any meaning? Whether their God has broken his covenant with his chosen people? And so the debate begins. Arraigned in a makeshift, but still legal - owing to the presence of the "living Torah" - court, God is put on trial. A trial that examines enough theological and philosophical questions to make your head spin.

I'm not going to reveal the verdict. If you didn't see it, you can catch it again on BBC iPlayer (for 7 days from now). I'll reveal my verdict though. A thoughtful subject, sensitively and thoughtfully handled with excellent performances from some of our finest actors. Adult drama for thinking adults. Top stuff.