‘She could go all the way, Siobhan, mark my words. There’s a lot you could learn from Gill Templer.’

‘Yes, sir. I’ll speak to you later.’

‘Bye, Siobhan.’

She put the phone down. ‘He’s going to mull it over,’ she told Grant.

‘Great, and meantime the clock’s ticking.’

‘Okay then, clever-clogs, let’s hear your great idea.’

He looked at her as if measuring the challenge, then held up a finger. ‘One, it reads to me almost like a story-line. Maybe from Shakespeare or somewhere.’ A second finger. ‘Two, does it mean “corny” as in old-fashioned, or is it maybe to do with where corn comes from?’

‘You mean where corn was first grown?’

He shrugged. ‘Or how it starts off life as a seed: ever heard the expression “sowing the corn of an idea”?’

She shook her head. He held up another finger.

‘Three, say it’s mason as in stonemason. Could it be a gravestone? That’s where all our dreams end, after all. Maybe it’s a carving of a corn-stalk.’ He bunched the raised fingers into a fist. ‘That’s what I’ve got so far.’

‘If it’s a gravestone, we need to know which cemetery.’ Siobhan picked up the scrap of paper on which she’d written the clue. ‘There’s nothing here, no map reference or page number …’

Grant nodded. ‘It’s a different kind of clue.’ He seemed to spot something else. ‘Could “a corny beginning” actually be “acorny”, as in like an acorn?’

Siobhan frowned. ‘Where would that get us?’

‘An oak tree … maybe oak leaves. A cemetery with “acorn” or “oak” in its name?’

She puffed out her cheeks. ‘And where would this cemetery be, or do we have to check every town and city in Scotland?’

‘I don’t know,’ Grant conceded, rubbing at his temples. Siobhan let the clue drop back on to the desk.

‘Are they getting harder?’ she asked. ‘Or is it that my brain’s packing in?’

‘Maybe we just need a break,’ Grant said, trying to get comfortable in the chair. ‘We could even call it a day.’

Siobhan glanced up at the clock. It was true: they’d put in about ten hours already. The whole morning had been spent on a wasted trip south. She could feel her limbs aching from the climb. A long hot soak with some bath salts and a glass of Chardonnay … It was tempting. But she knew that when she woke up tomorrow, there’d be scant time left before the clue was void, always supposing Quizmaster stuck to his rules. The problem was, the only way to know whether he would or not was to fail to solve the clue in time. It wasn’t the sort of risk she wanted to take.