Period drama returns for final series: 'We wanted to end on our own terms'

It is also, and this should not be underestimated, very funny. The humour comes from character rather than jokes, and it arrives exactly when the tension needs releasing.

The ending will divide people. Some will find it too abrupt, others too neat. I found it exactly right: an answer to a question the film had been asking, very quietly, from the beginning.

Nothing is wasted. Every shot, every line, every silence is doing something

It is rare to encounter something this confident, this fully realised, that does not seem to be trying to impress you. It simply is what it is, and trusts you to meet it there.

Whether it finds the audience it deserves is another matter. But those who do find it will, I suspect, hold on to it for a long time.

A singular vision

It begins quietly, almost apologetically, and for the first 20 minutes you may wonder whether anything is going to happen at all. Then something does, and from that point on it is impossible to look away.

What makes it remarkable is not the plot, which could be summarised in a sentence, but the precision with which every element has been arranged. Nothing is wasted. Every shot, every line, every silence is doing something.

The central performance is a marvel of restraint. There are no big speeches, no obvious moments of catharsis, just a slow accumulation of small choices that, by the end, has become almost unbearably moving.

"I wanted it to feel like a memory," the director told me when we met in a cafe near the festival venue. "Not a story somebody is telling you, but something you half remember happening to you."