We watched it again, and again, and again, until even I felt a wave of nausea. The room had fallen into a thick, attentive quiet. Camilla’s eyes looked wet.

Another of the girls said, ‘Aleks, hey, can I go? I’ve got —’

His look silenced her. ‘We can all go,’ he said, ‘once Camilla has identified her error. Come on, it’s not that hard. It’s something you’ve done dozens of times. Hundreds, probably. Well?’ he said.

Camilla scratched her neck, and I heard the scratching, imagined the scraped-off cells collecting under her fingernails.

‘She’s diving blind,’ I blurted out.

You’re supposed to keep your eyes open when you dive. It’s so you can find visual cues and orient yourself as you fall. Diving blind – that is, with your eyes shut – is a common mistake.

Everyone turned to look at me. Grace gave a minute shake of her head. Shut up, she was saying. Shut up.

I wondered if I’d be asked to leave. Camilla gave me a look that may have been relief or may have been loathing.

Aleks gave a curt nod. ‘Thank you, Joan,’ he said, ‘for putting us out of our misery.’

As we were walking out, Grace said to me, ‘He’s kind of a prick. But she always does that.’

‘Dives blind?’

‘Plays dumb.’

‘Oh.’

We’d fallen behind the others. We took a few more steps in silence before Grace said, ‘They’re fucking, you know.’

‘What?’

She smiled. Her skin shone from the sorbolene. ‘You heard me,’ she said.

In the training sessions that followed, I wondered about the truth of Grace’s claim. I watched Aleks and Camilla carefully, but there was nothing in the way he treated her that suggested any tender feeling. In fact, there were times when he seemed disgusted with her, shaking his head, turning his back. Even when she started to keep her eyes open, improving her overall execution as a result, he still managed to exude contempt.

Soon enough, I was able to experience his lack of mercy for myself. It turned out that this was the quality I liked best about him. I liked the way he barked ‘Now’ when he wanted me to come out of a dive. I liked how he would approach me while I was on the lat pull-down machine and push his fingers hard into the centre of my spine, not letting me release until I had pulled the bar all the way into my sternum. I liked that when he was impressed he didn’t say so, just betrayed it through a surprised flick of both eyebrows.

When I failed in front of Aleks, smacking, coming out too late or early, missing my cues, I burned with shame. He never laughed it off, never reassured me. He would just peer down his nose as I dragged myself out of the pool, a stony look on his face.