The response was a furious rattling and sloshing. The metal box was secured by yet another padlock, drawing another sigh from the locksmith. ‘Let’s get the whole thing out of here,’ Gillard said. With the help of a tow rope from one of the police vehicles, and the strength of Tunnicliffe at one end, they managed to haul the box from the inspection pit. The water sloshing around inside made it almost impossible to keep level, but they slid it across the floor of the workshop until there was space to work on it. The locksmith had bad news: ‘The lock’s been superglued, we’ll have to cut it off.’

‘We can’t use the blowtorch, it’ll cook her,’ Gillard said.

‘Fire service two minutes away,’ Hoskins said.

‘Let me try,’ Tunnicliffe said. The box was well made, with a flanged lid and no gap big enough for the tip of the crowbar. There was nowhere for the big man to get any purchase to lever up the lid.

‘Quick, the electric drill,’ Gillard said.

The locksmith obliged, drilling ten quick shallow holes low in the side of the box. Water jetted from within. The kicking and rattling continued.

‘Sam, if you can hear me in there. You’ve just got to hang on. The water’s being drained out.’ He feared that she might die of exposure because of the freezing water, even if she didn’t actually drown. He couldn’t imagine any worse way to go than drowned in claustrophobic darkness. Buried alive, but worse.

Sound of sirens and air horns in the distance proclaimed the arrival of the fire service and an ambulance. Tunnicliffe manually hauled up the roller door again to see a young man sprinting past the many parked police vehicles blocking the access road. He had on a fire service brown jacket, and carried a toolbox.

Two minutes later, with the help of hydraulic cutters, the lid was opened. Sam was inside, drenched, bound almost head to foot in gaffer tape, only her nose clear, arms locked in front of her by cable ties. Gillard borrowed a Stanley knife from the locksmith, and carefully cut the tape from her face. The moment her mouth was free, sobbing began, and he hauled her out and into his arms. For a long time she couldn’t speak, but simply clung to him, her eyes squeezed shut against the unaccustomed light. Everyone else stood back to give them a little space. Her body was frozen, her fingers and toes blue with cold. He carried her over in front of the warm air blasting from the chillers, and let the paramedics do their job. For the next forty-five minutes he held her hand while she was wrapped in warm dry blankets and put inside an exposure bag. He stroked her hair and kissed her cheek.

Eventually, he stood back and watched her being taken into the ambulance. For a moment he watched his colleagues, many of whom were now working again on the ice. Perry, his daughter still missing, was working away at the slushy mass. ‘Who is she?’ said the female officer working at his side, sweat coursing down her brow as she wielded the screwdriver.