Often Timmy had rebelled, throwing himself on the floor, crying and defiantly ignoring the ‘tidying for playing’ deal.

Anouk was obstinate too. She wanted the torch. But she wasn’t yet ready to trust him.

She stared at him grimly with a deep frown.

‘Okay, I’m going to tell you what happened,’ Martin said. ‘I think you know where your mother is. You even drew the place for us, on your toy computer, although we didn’t understand your clue and we don’t know where this shaft is. But you know the way. You marked it with the UV pens that I found in your pencil case. Unfortunately, these marks can’t be seen with normal light…’

When he made the mistake of briefly glancing up at the overhead light, he was suddenly struck by a flash. The adverts claim that there are thirty-seven types of headache that can be treated with non-prescription medicines. Clearly this wasn’t one of them. It felt as if someone were sticking very thin, red-hot needles from the inside of his head through his eyes to the other side of the pupils. Martin even thought he could feel the points of the emerging needles, bloodily tearing the insides of his lids whenever he blinked.

Leaning against the door, watched mistrustfully by Anouk, who was standing as if rooted to the basin, he waited until the pain had subsided to a tolerable level. Then he turned off the light.

The darkness was a relief. His headache faded to a pale shadow of itself. The attack died away as quickly as it had come.

He briefly allowed his eyes to get used to the almost complete darkness. Then he turned on the torch. And the beam that was barely visible in normal light suddenly filled the entire room, making the white bathroom tiles fluoresce, as well as Anouk’s nightshirt, teeth and fingernails.

Pens. Drawing. Torch.

‘I knew it,’ Martin said to himself. There was no hint of triumph in his voice when his theory proved correct. Anouk’s eyes shone spookily in the black light. She looked like a ghost without lips from a horror story.

The torch he was aiming at the girl wasn’t weak, but a UV lamp shining light at a frequency barely visible to the naked eye. He’d once used a similar model on an operation.

But where did Anouk get these torches from?

A question he had to postpone, for now there were more important things to clear up. ‘It showed you the way to your mother, didn’t it?’

When Anouk failed to react, he asked insistently, ‘Where was she taken to?’

Anouk’s response pulled the carpet from under his feet again. For, just as at their first meeting, she whispered his name again.

‘Martin.’