Wolf neatly folded a change of clothes and put them in the bottom of his knapsack. He packed several homemade energy balls; he made them every week out of seeds, coconut oil, chocolate and dried fruit. He also packed a bar of soap, a toothbrush, a tiny battery-operated radio, a length of rope, some water-purification tablets, his Swiss Army knife, a small can of WD-40, a magnifying glass, a notebook and pencil, an OS map of the Borders from Leonard Levar’s maps section, an old phone with a flashlight function and a dictionary, and a small bag of bloodstones. He filled his old army canteen with water from the tap and attached it to his knapsack.

It was now quarter past eight. Wolf had almost finished packing. All that remained was adding his Sword of Orphennyus, in its benign form as a letter opener, to the side pocket of his knapsack, where he could get it easily. Wolf had to wear a special glove when he touched it: any contact with a true warrior caused the sword to grow to full size. He packed the glove in the other side pocket.

He washed quickly and dressed in his jeans, a T-shirt, a hoody and his battered old bomber jacket. He wore his sturdiest, most comfortable, waterproof duty boots, which he’d got from the army surplus shop in the Old Town.

Wolf’s walk to the bus station was a bit of a blur. There was snow: It had come overnight. But his boots powered through it; their special soles didn’t skid on ice. As he walked, Wolf kept thinking about Natasha. If he could save her . . . If he could give her a better life . . . But maybe she didn’t need saving. Maybe Wolf’s mother had gone off and married a rich man. Maybe Natasha was having a great life. But that wasn’t how Wolf remembered his mother. She was always caught up with the wrong men, in the wrong situations. Maybe Wolf could help her, too. He still hadn’t forgiven her for leaving him with his uncle. He just wanted to get his sister and look after her.

In less than half an hour, Wolf was on a bus to the Borders. He’d been lucky. When he read the timetable, he found he’d picked the best bus and wouldn’t even have to change. Through the steamed-up windows Wolf could see that the whole city was covered in snow. But the streets were clear, and the bus chugged on.