‘Soon as you’ve fired the flare,’ said the eldest of the group, a beardless, sharp-featured man called Peter who was the field leader, and who spoke in a state of permanent fortissimo, ‘bang the pan with the ladle. Bang it like mad and scream. They have sensitive hearing. They’re like cats. Nine times out of ten, the noise scares them off.’

‘And the other time out of ten?’

He nodded down at the rifle. ‘You kill it. Before it kills you.’

Nora wasn’t the only one with a gun. They all had guns. They were armed scientists. Anyway, Peter laughed and Ingrid patted her back.

‘I truly hope,’ said Ingrid, laughing raspily, ‘you don’t get eaten. I would miss you. So long as you aren’t menstruating, you should be okay.’

‘Jesus. What?’

‘They can smell the blood from a mile away.’

Another person – someone who was so thoroughly wrapped up it was impossible to tell who they were even if she had known them – wished her ‘good luck’ in a muffled far-away voice.

‘We’ll be back in five hours . . .’ Peter told her. He laughed again, and Nora hoped that meant it was a joke. ‘Walk in circles to keep warm.’

And then they left her, walking off over the rocky ground and disappearing into the fog.

For an hour, nothing happened. Nora walked in circles. She hopped from left foot to right foot. The fog thinned a little and she stared out at the landscape. She wondered why she was not back in the library. After all, this was definitely a bit shit. There were surely lives where she was sitting beside a swimming pool in the sunshine right now. Lives where she was playing music, or lying in a warm lavender-scented bath, or having incredible third-date sex, or reading on a beach in Mexico, or eating in a Michelin-starred restaurant, or strolling the streets of Paris, or getting lost in Rome, or tranquilly gazing at a temple near Kyoto, or feeling the warm cocoon of a happy relationship.

In most lives, she would have at least been physically comfortable. And yet, she was feeling something new here. Or something old that she had long buried. The glacial landscape reminded her that she was, first and foremost, a human living on a planet. Almost everything she had done in her life, she realised – almost everything she had bought and worked for and consumed – had taken her further away from understanding that she and all humans were really just one of nine million species.

‘If one advances confidently,’ Thoreau had written in Walden, ‘in the direction of his dreams, and endeavours to live the life which he has imagined, he will meet with a success unexpected in common hours.’ He’d also observed that part of this success was the product of being alone. ‘I never found the companion that was so companionable as solitude.’

And Nora felt similarly, in that moment. Although she had only been left alone for an hour at this point, she had never experienced this level of solitude before, amid such unpopulated nature.

She had thought, in her nocturnal and suicidal hours, that solitude was the problem. But that was because it hadn’t been true solitude. The lonely mind in the busy city yearns for connection because it thinks human-to-human connection is the point of everything. But amid pure nature (or the ‘tonic of wildness’ as Thoreau called it) solitude took on a different character. It became in itself a kind of connection. A connection between herself and the world. And between her and herself.

She remembered a conversation she’d had with Ash. Tall and slightly awkward and cute and forever in need of a new songbook for his guitar.

The chat hadn’t been in the shop but in the hospital, when her mother was ill. Shortly after discovering she had ovarian cancer, she had needed surgery. Nora had taken her mum to see all the consultants at Bedford General Hospital, and she had held her mum’s hand more in those few weeks than in all the rest of their relationship put together.

While her mum was undergoing surgery, Nora had waited in the hospital canteen. And Ash – in his scrubs, and recognising her as the person he’d chatted to on many occasions in String Theory – saw she looked worried and popped in to say hi.

He worked at the hospital as a general surgeon, and she’d ended up asking him lots of questions about the sort of stuff he did (on that particular day he’d removed an appendix and a bile duct). She also asked about normal post-surgery recovery time and procedure times, and he had been very reassuring. They’d ended up talking for a very long time about all sorts of things, which he seemed to sense she’d been in need of. He’d said something about not over-googling health symptoms. And that had led to them talking about social media – he believed that the more people were connected on social media, the lonelier society became.

‘That’s why everyone hates each other nowadays,’ he reckoned. ‘Because they are overloaded with non-friend friends. Ever heard about Dunbar’s number?’

And then he had told her about a man called Roger Dunbar at Oxford University, who had discovered that human beings were wired to know only a hundred and fifty people, as that was the average size of hunter-gatherer communities.

‘And the Domesday Book,’ Ash had told her, under the stark lighting of the hospital canteen, ‘if you look at the Domesday Book, the average size of an English community at that time was a hundred and fifty people. Except in Kent. Where it was a hundred people. I’m from Kent. We have anti-social DNA.’