There’s none of the wisdom and chatty intimacy that Nicolas enjoyed with his predecessor. In any case, Nicolas rarely goes to church these days – now and again at Orthodox Christmas, and mainly because he likes the music.

Volchkov has moved to Lyon. Rachkovsky’s gone entirely. He vanishes from this story, leaving a mask to be worn by other antagonists.

Paris falls in June 1940. Anya is too frail to leave. Since her terrible decade of loss, she’s found it increasingly hard to leave the house. Unfamiliar places seem full of unspeakable menace. It is a form of mental illness. Nicolas has long since given up attempting to reason with her delusions. He cares for her in their apartment: a much smaller one, in which piles of his books form teetering internal walls.

In the aftermath of military defeat, an old theme emerges. There has already been some grumbling that the Notovitches’ remaining son is abroad and not doing his bit for France. Now the recrimination is more overt: ‘On nous a vendu,’ goes the muttering. ‘Sales youpins.’ They sold us out. The dirty Jews.

By October, Jewish businesses are forced to display bilingual signs in the windows. Entreprise juive. Jüdisches Geschäft. Under the Statut des Juifs, foreign Jews must register their names and places of birth at the police headquarters.

Nicolas wisely chooses to ignore the order. He tries once more to sell the department store with the hope of raising money to emigrate. Someone offers him a ten per cent down payment, changes the locks, and then reports him as a foreign Jew to avoid paying the rest.

He reassures Anya. Father Gerasim will have proof of their baptisms and marriage. They will straighten this thing out: perhaps join Volchkov in Lyon while the unpleasantness subsides. He finds Gerasim in the vestry. The priest listens without expression and replies unhurriedly.

‘You’ve not been to church for a while,’ he says. ‘I have a proposal: I’ll find the paperwork that shows your parents are Orthodox believers from beyond the Urals, born east of the Pale, in the land where no Jew ever set foot. In return, you repudiate the lies in your book.’

How long has Gerasim been cooking up this plan? He’s an opponent of heresy, innovation and woolly thinking. The position of the Church is very clear: submit to tradition or take your chances on Judgement day. Religion is not a menu à la carte.

The old man blazes, suddenly young. ‘You whippersnapper! How dare you!’ Gerasim turns his back until he hears the door shut.

Upon reflection, Nicolas realises he must do as the priest asks. If he’s drawn a conclusion from his life, it’s that a human being is worth more than any mere idea. But now it’s too late.

On 7th June 1942, Parisian Jews are legally obliged to buy and wear the yellow six-pointed Star of David. They pay for it with clothing coupons. Jews are banned from public places and subject to curfew between 8 p.m. and 6 a.m.