‘I don’t think anyone else is here,’ Ethan said, searching through the kitchen cupboards. ‘Help me find something to tie him up, and then we’ll look upstairs. Handcuffs’d be great, but I don’t think we’re going to find any …’

‘Next to the kettle?’ Thea picked up a pair.

They both stared at them.

‘Okay then.’ Ethan raised an eyebrow.

A noise by the door caused them to both whirl round, just in time to see the guard on his feet wrenching the door open and stumbling out into the sleet.

‘Shit.’ Ethan ran to the door.

‘Let him go.’ Thea shrugged, marvelling at how cool she could act. ‘What’s he going to do? They already know we’re here. He’d just be one more thing to worry about.’

She started to rummage through the plastic box of medicine on the kitchen worktop.

‘There’s enough sedative here to last for months …’

She trailed off as they both looked at each other. Who, or what, would need sedating? Thea half expected cold fingers to wrap themselves around her shoulder. She shivered.

‘We need to check upstairs.’ Ethan took the packet from her and glanced at the instructions. ‘You can stay down here if you want.’

‘No!’

Ethan went first. Action Ken, that’s what Rosie had called him. It had made Thea laugh at the time, the idea of him in a camouflage outfit, poseable arms holding a pair of binoculars, plastic attack dog included.

Thea’s hands started to shake. They passed another little room wedged in around the stairs on the second floor, this time a sparse bedroom. Inside was a single bed, plain woollen coverlet and a few clothes strewn on a hard-backed chair. They carried on up towards the light. Thea couldn’t stop the shaking spreading from her hands to the rest of her, in particular her jaw. She tried to clench it, but it juddered like she was the kind of cold that led to freezing to death.

They made it to the light-room, the intricate structure of glass panels and machinery in the middle, a narrow walkway around it.

That was when Thea started to gulp in air because it felt like she couldn’t breathe properly anymore. Because of the gulping and the shaking, she found herself half-sliding to the floor in a panic, no clue as to why she was suddenly on her hands and knees on the metal walkway, the grids cutting into her palms, her chest heaving, trying to suck in air like she was giving birth.

‘Shh, it’s okay. You’re having a panic attack. You’ll be fine …’

Ethan pushed her into a sitting position and sat with her, making her breathe with him, long steady breaths, and there was a part of her that was cringing in embarrassment, but she couldn’t worry about that part until she got control of her lungs.