‘This has sort of happened to me before, you know,’ Ben said, a little more loudly, as they both pretended not to be able to hear Ellen from behind the mirror. She had definitely started. Ben’s eyes were tired but danced.

‘Oh yeah?’ Alexa replied. She noticed for the umpteenth time the deep dimple in his chin. It was about the size of the tip of her thumb, and seemed to get deeper when he smiled, which was often.

‘Yeah, really.’ He was eager to convince her. ‘Though strictly, it was a greenhouse, not an attic. My uncle’s, in his garden, in Devon. We used to go there all the time when we were small. Anyway, some mechanism in the ancient door broke and Ava – my sister – and I got trapped in there. In the end, my mum had to smash one of the panes, and she yanked the handle open from the outside. I seem to remember we found it rather funny.’

‘And was it your fault that time too?’ Alexa replied, like quicksilver.

Ben laughed, a high clear note. ‘Definitely not. All Ava’s.’

Alexa smiled. ‘How long were you in there for?’

‘An hour or so, I reckon. But I was about eight and Ava would have been six. So to us it probably seemed like for ever.’ He smiled at Alexa. ‘I remember Ava eating lots of my uncle’s tomatoes off the vine. He was furious.’

They could still hear Ellen.

‘So you were well taken care of, then.’ She tried to ignore the sound. ‘Tomatoes on tap.’

‘Absolutely. Couldn’t have asked for better rations …’ She sounded like she was stopping. ‘How long do you think we’ve been up here for now?’

Alexa wrung her blank wrist where her watch usually was. ‘No idea. It’s probably time to take over from Jack, though. He’s been there a while.’

‘Only fair.’ Ben cleared his throat and spoke a little louder. ‘Hey? Jack?’

Jack turned, expectantly.

‘What time is it, mate?’

Jack consulted his phone, looking anxious. ‘Nine thirty-five.’

Alexa smiled encouragingly at him.

‘Great. I’ll take over in a minute, OK?’

‘Oh.’ Jack sounded surprised. ‘Well, thanks,’ he added, after a pause.

‘Nine thirty-five.’ Ben groaned. ‘We should definitely still be asleep.’

‘Oh, I don’t know,’ Alexa said. The way he watched her when she spoke made her feel like she wanted to talk for ever. ‘I quite like getting up early on a Saturday. Making the most of the weekend.’ Now he was looking at her as though she was mad. ‘I’m not very good at lie-ins,’ she finished, lamely.

‘I am very, very good at lie-ins. Don’t worry.’ He nudged her, lightly, in the ribs and she felt her whole body buzz. ‘I can teach you.’