Rowlinson discarded the card, which turned out to be concealing another set of words. This time, the words had been crudely etched onto the metal safe by something sharp.

They examined it further.

Priest read and exhaled loudly.

RULES:

DO NOT OPEN THE SAFE.

DO NOT MOVE THE SAFE.

CHOOSE ONLY ONE BUTTON.

‘Ah, Christ,’ Rowlinson breathed.

Without warning, the digital display lit up with a reading.

0.59.

‘Jesus. It must have been triggered when I pulled the card off.’

Priest inspected the back of the box. Two black wires trailed off down the back, splitting at the base and going in separate directions. He traced them back around to the front of the safe, lifting them upwards off the ground and moving them to a clump of grass a few metres behind them.

Rowlinson peered over his shoulder. ‘Holy God. There’s enough explosives here to send us to Hell and back.’

The charges were set in a semicircle where the cliff jutted out above the waves crashing on the rocks below. The intention was clear. If the explosion didn’t kill them instantly, then the whole of the cliff face would break off and be washed away, along with whatever was on it.

Priest turned back to the safe and as the last sliver of light from the sun vanished into the sea, the countdown continued.

0.58

0.57

0.56

‘Which button?’ Rowlinson said urgently. ‘It says choose one. Up or down?’

Priest looked at the box again. Karl had put the contraption together himself, wired it pretty well. The box was bolted onto the safe, so no prospect of lifting it off. Pulling the wires out was possible but likely to result in the charge going off.

A breeze had whipped up in the absence of the sun and he felt his brow starting to melt. Rowlinson shuffled around behind him, panicking.

‘Come on, Priest! You know this bastard. Which button?’

0.44

0.43

Priest closed his eyes and saw Karl’s face. He was big, awkward to talk to, obsessive, a computer geek. Come on, think! He thought about the diary. Could Karl have written it? Was that why it’s written in the third person? But where did he get the detail from?

He dismissed the idea – which means if Karl didn’t write it, then who? Elinor?

‘This is his grand finale,’ he muttered.

‘Yes! I know – like you said. Up or down?’

0.35

0.34

‘Down means we all get blown into the water. I say we pick up,’ cried Rowlinson.

‘Up as in blow us all sky-high?’

Rowlinson was hovering around the box, his hands flapping dangerously close to the buttons. Priest positioned himself between the detective and the safe, lest he make a rash decision.

No need to be rash. Just need to be logical.

‘How did Elinor survive?’ he asked, although more to himself than Rowlinson.

‘I don’t know!’ shouted Rowlinson, exasperated. ‘Must have been a fluke. Maybe she missed the rocks and was washed up on the beach.’

0.28

0.27