They turned off the main road and drove into the village of Roslin. Siobhan parked the car beside the chapel’s gift shop. The door was locked tight.

‘Place doesn’t open till ten,’ Grant said, reading from the notice. ‘How long do you reckon we’ve got?’

‘If we wait till ten, not very long.’ Siobhan was sitting in the car, checking that there were no new e-mails for her.

‘There must be somebody.’ Grant banged on the door with his fist. Siobhan got out of the car and studied the wall surrounding the chapel grounds.

‘Any good at climbing?’ she asked Grant.

‘We could give it a go,’ he said. ‘But what if the chapel’s locked too?’

‘What if someone’s in there giving it a quick spit and polish?’

He nodded. But then there was the sound of a bolt being drawn back. The door opened and a man stood there.

‘We’re not open yet,’ he said sternly.

Siobhan showed him her warrant card. ‘Police officers, sir. Afraid we can’t wait.’

They followed him along a path towards the chapel’s side door. The building itself was covered with a huge canopy. From her previous visit, Siobhan knew there was a problem with the roof. It had to dry out before work could be done on it. The chapel was small on the outside, but seemed larger inside, a trick of its ornate decoration. The ceiling itself was stunning, even if much of it was green with damp and decay. Grant stood in the central aisle, gawping much as she had done the first time she’d come here.

‘It’s incredible,’ he said quietly, his words echoing back off the walls. There were carvings everywhere. But Siobhan knew what she was looking for, and walked straight towards the Apprentice Pillar. It was next to some steps leading down to the sacristy. The pillar was about eight feet high, carved ribbons snaking down it.

‘This it?’ Grant said.

‘This is it.’

‘So what are we looking for?’

‘We’ll know when we find it.’ Siobhan ran her hands over the cool surface of the pillar, then crouched down. Intertwined dragons were coiled around the base. The tail of one of them, twisting back on itself, had left a small nook. She reached in with finger and thumb and brought out a small square of paper.

‘Bloody hell,’ Grant said.

She didn’t bother with gloves or an evidence bag, knew by now that Quizmaster wouldn’t have left anything useful to Forensics. It was a piece of notepaper, folded over three times. She unfolded it, Grant shifting so they could both see what was printed there.

You are the Seeker. Your next destination is Hellbank. Instructions to follow.

‘I don’t get it,’ Grant said. ‘All of this, just for that?’ His voice was rising.

Siobhan read the message through again, turned the paper over. Its other side was blank. Grant had spun on his heels and kicked air.