‘Tom,’ she called out, realizing she was crying. ‘Tom, please. It really isn’t funny.’

Tom didn’t answer her, and she carried on along the landing.

Tom was running, terrified he’d lose sight of Ebba and be left alone in the clawing, creeping darkness. He had no idea how big an underground chamber he was racing through, he couldn’t see the walls – not that he was looking; his eyes were fixed on the girl ahead of him.

Every time Tom was tempted to turn back, he made himself think of his brother. Joe, who he sometimes thought had been sent to earth to make his life miserable, who had been a complete pain from the day he was born, who was always getting his own way and who he fantasized about killing at least once a week. Joe, who he really didn’t think he could live the rest of his life without.

A wall loomed in front of them and Ebba shot through an archway. Tom went too, before he had chance to ask himself whether this was a good idea or not. None of this was a good idea, it was probably the worst idea he’d ever had in his life, but the strange creature ahead of him had his brother’s shoe.

She was balancing on an upturned crate and reaching for something in the ceiling. Then Tom saw light shining through. A minute later he and Ebba were both in the church. There was no sign of the police constable, the door to the vestry was firmly closed. Then Ebba was on her feet again and running up the aisle towards the back of the church.

Tom wasn’t in the house. Alice had been right and Evi had wasted precious time. She hadn’t even seen a phone. Nor had she heard anything of Alice for several minutes now. She had to get back downstairs and call the police. They could be here in minutes. She would use her mobile – it was just outside, in her car.

As she approached the front door, it slammed shut, startling her. She took a second to catch her breath. There was still a cold wind blowing through the house. Then the door of the living room blew shut.

She crossed the hall and pushed it open again. The window at the far end of the room was wide open. As quickly as she could, Evi walked across the room and leaned out. There was no sign of Alice in the garden any more.

‘Tom!’ Evi called.

Tom didn’t reply, nor had Evi expected him to. Tom had gone. A clear set of footprints leading across the garden to the churchyard wall, far too small to have been made by an adult, was indisputable proof of that.

Evi leaned out further and looked at the ground more closely. A second pair of prints lay in the snow just to one side of the boy’s. Knowing how much it would hurt, Evi sat on the window ledge, swung her legs up and twisted round until she could lower herself into the garden.

Already the snow was beginning to cover the prints; in less than an hour they might hardly be visible at all. Now, though, they were clear enough. Not very long ago, someone had crossed the garden from the wall and had then turned and retraced their steps, taking Tom along too. Tom’s footsteps were clean and regular, with no indication that he’d been dragged or forced along. Evi peered at the second set of prints. They were adult sized, although not huge, and quite different to the swirled and ridged pattern made by the soles of Tom’s trainers. Evi could see the outline of a large big toe, the curve of an instep. These were the prints of someone who didn’t wear shoes.

Tom had gone with Ebba.

The door gave way on the fourth blow and Harry caught hold of Gareth by the shoulder to stop him racing in. ‘Bore hole,’ he reminded him.

Pushing himself in front, Harry shone his torch all around the small stone hut. It had just one room, about four metres long by three wide. Looking up, he could almost touch the beams of the roof. A large metal ring had been screwed into the central beam. Under their feet was pitch-pine flooring.

Gareth moved in, banging the floorboards with the heel of his boot.

‘Sounds pretty solid,’ said Harry.

Gareth shook his head. ‘This is different,’ he said.

Harry listened as Gareth moved from one spot to the other, banging his foot down hard on each. The difference was minimal.

Harry began moving slowly round the hut, shining his torch downwards, looking for any discrepancies in the boarding that might indicate that the floor could be raised. There was nothing that he could see. Except, eighteen inches in from the door, there was a small round hole in one of the boards. He bent down.

‘What is it?’ asked Gareth.

Harry’s little finger was circling round in the hole. ‘Screw hole,’ he said after a second. ‘I can feel the thread. Something is supposed to screw into here.’ He looked up, shining the torch around, as though whatever was supposed to be screwed into the hole might be lying conveniently by on a hook. ‘Something like that,’ he said, shining the torch directly at the ring in the roof beam.

Gareth glanced up and then moved to the back of the hut. ‘Like this,’ he said, pointing at a similar ring that had been fastened into the rear wall. Several feet below the wall ring was a twisted piece of metal. ‘This is a lifting mechanism. Give me that rope.’

Harry tossed the rope over and watched the other man thread the end through first the wall ring and then the roof-beam ring. Then he brought it over to where Harry was kneeling.

‘This ring’s missing,’ said Harry.

‘Of course it is,’ said Gareth. ‘With the ring here, it would be too easy to access the bore hole. It was probably removed for safety. Or Gillian could have it.’ He dropped flat on the boards. ‘Joe!’ he yelled. ‘Joe!’

Harry couldn’t stop himself shuddering. Gareth was pushing himself to his feet again, reaching out for his tool-box, taking out a sharp chisel and hammer. He pushed the sharp end into the gap between two boards and slammed the hammer down hard. The wood splintered. Gareth banged again and again. Then he stopped, found another chisel and hammer and threw them to Harry. ‘Other side,’ he ordered.

Harry found the tiny, narrow gap and started copying. The wood was old and crumbled easily enough. After hammering through just over an inch of wood, the chisel almost slipped from his hand.

‘I’m through,’ he said. ‘It’s hollow underneath.’ Gareth was already threading the end of the rope through the hole he’d made and aiming it towards Harry. Harry stuck his fingers into the gap, fumbling around until he felt the rope. He tugged and it came.

Taking it from him, Gareth tied the end together and then jumped up and strode to the other side of the hut. He looked at Harry. ‘Stand back,’ he said. ‘Next to the wall.’

Shuddering with every step, Evi was back in the house, intent on getting her mobile phone from her car. As she opened the front door, she had to clutch at the frame – she was going to fall any second now. A dark shape appeared from around the side of the house.

‘Alice?’ Evi called, uncertain. Too tall to be Alice.

‘It’s me.’ A woman’s voice. The figure stepped into the light. Jenny Pickup, Alice’s friend. She’d been here earlier, helping with the children. Thank God.

‘Jenny, Tom’s missing too.’ Evi found herself ridiculously short of breath, every word an effort. ‘We have to get help,’ she managed. ‘He’s gone with that girl he’s been talking about, the one with the hormone deficiency. The one who’s been hanging around the house.’

Jenny frowned for a split second and looked back over her shoulder. Then she stepped forward. ‘Evi, you look dreadful,’ she said. ‘Come back inside. Let me get you something.’

‘We have to call the police. Tom’s missing. I have no idea where Alice is.’

Jenny put a hand on the door, the other on Evi’s arm. ‘Take it easy,’ she said. ‘Get your breath back. The police are on their way.’

‘They are?’

‘Yes, absolutely,’ replied Jenny. ‘I called Brian myself. He said ten minutes. Now, Alice asked me to check on Millie. And you really need to sit down.’