The next day, he ditched the itinerary, going off-piste to see a ballet with Darya at the Mariinsky Theatre. It was her idea; Paul was not a ballet fan. Nikolai was to join them but he expected to come late. Things were coming to a head at his company, Zolotneft. Darya had left him talking things over with her father, who, as a state geologist turned senior bureaucrat, had experience in the sector. It was quite a coincidence, Paul mused, that Darya’s dad was so well placed to be useful to Nikolai. But he couldn’t pretend to be sorry to have Darya to himself, and he shot a text to Julius to make his excuses.

He and Darya caught a bus from Nevsky Prospekt, and he felt childishly happy to be in her company. Arriving early, they strolled to the English Embankment, and as they walked along the Neva River he began to feel a strange sense of insurrection. He had always been a person of moderate wants, yet as they walked to the river (keeping a safe distance from each other), he was aware of wanting Darya more than ever, beyond reason. He didn’t want to stick to the deal they’d struck, didn’t want to be her friend.

Preparing to say as much, he glanced at the darkening river and remembered something he’d read about it – that although it looked like it flowed east, this was just an illusion, a trick of the wind, and in fact the current ran very strongly west, towards the Gulf of Finland and the Baltic Sea. He was like this river, he thought, with an unseen current: he had never really been all that moderate, not as even-tempered as others thought. He could want things as badly as any person on earth.

But they had wandered too far, forgetting the time. Now they had to power-walk back to take their seats in the theatre. Onstage Giselle flounced and leapt, an improbably doll-like athlete. A slender-thighed Albrecht was stronger than he looked, eliciting flurries of applause. Paul joined in the clapping, impatient for the intermission, but when it finally came so did Nikolai. He met them in the foyer, with his furrowed brow, his own overriding atmosphere of drama, and after greeting Paul he hurried Darya outside to talk to her privately. Through the glass, Paul saw him thrusting papers at her. He watched with dread as he saw Darya turn pale. He wondered if it was something to do with Nikolai’s work, though he’d never had a sense of her being involved with that.