There was a small silence. ‘In that case,’ Oliver answered, ‘what are you asking me for? If you’re not going to drink any more, I’ll finish the bottle.’

Tom’s fingers grasped the neck of the decanter before he passed it over. ‘I’m not asking you. I’ve just realised. I’m telling you. And you won’t finish the bottle, because I’m going to.’

Oliver yawned. ‘Anything you like. So long as you stop treating me like an agony auntie.’

With the laughter, Tom saw that his way was clear. At once his headache lifted. For a single moment everything seemed simple, and he was filled with affection for Oliver, the dark club-room, and the whole world. He would be with Helen. He wouldn’t let her slip away, because he couldn’t.

‘Not time to go yet, is it?’ The warm fingers of drunken euphoria began to wrap themselves around him.

‘Definitely not.’

Much later, they stumbled back to Christ Church together. There was a lightness between them which had been missing for months. Oliver seemed his old, reckless and cheerful self. If he can still be like this, Tom thought dimly, there can’t be so very much wrong with him.

They clattered through the porter’s lodge together, elaborately signalling each other to silence and suppressing snorts of laughter like a pair of truant schoolboys.

In the rooms overlooking Canterbury Quad, Tom lurched against the mantelpiece and then mumbled, ‘What a long way off North Oxford seems. Think I’ll just sleep on your couch here. Sleep, lovely sleep.’

Oliver was leaning crookedly against the bedroom door. ‘Be my guest. See if you can drag me to the Schools by nine-thirty. What an extremely funny prospect.’

Tom was already plunging into sleep when he heard Oliver talking as collectedly as if he was quite sober.

‘It wouldn’t have worked anyway, you know.’

‘Wha’?’

‘My brother. And Helen. I never thought they quite matched, although I don’t envy you the prospect of unmatching them with the full weight of the Court and Social behind them. Darcy’s too straight, and Helen’s too loyal. Mmmm, Helen. Sorry I missed my own chance. Story of my life.’

‘Oliver?’

‘Yeah?’

‘Go away.’

The morning came. Helen watched the light intensifying at her windows and counted off the hours as they struck.

Her mind was as clear as crystal now. The week lying ahead of her was the important thing. She wouldn’t sacrifice that to anyone. Not anyone. Helen and Chloe met on the gallery, dressed in the regulation subfusc costume for sitting University exams. Black stockings, black skirt and jacket, white shirt and black tie, worn with cap and gown.