‘What about those who were sitting on the other side of the table?’

‘We don’t need theirs.’

‘Why not?’

‘Think about it, detective, and let me know when the penny drops.’

‘Do you know where that expression originates?’

‘Yes, I do,’ said William.

‘So, where should I start looking for prints?’

‘The water tumblers, the wine glasses and then the coffee cups, remembering the waiters wear gloves, so that eliminates them.’

‘And after I’ve done that?’

‘I’ll double-check the prints you find on Hamish’s hip flask. Once I’ve identified all of them, we’ll know if your theory stands up.’

‘And if it doesn’t?’

‘Then your grandfather died of a heart attack, and I shall inform the commodore that I have no reason to suspect foul play.’

‘And what if Grandfather’s prints aren’t on Hamish’s flask?’

‘Then I’ll need you and Franco to carry out a surveillance exercise for me.’

‘What do you have in mind, sir?’ asked Franco, as he poured William a second cup of coffee.

‘When Dr Lockhart comes down for breakfast this morning, I’ll go straight to deck seven. If he looks as if he might be returning to his cabin, James, you come up as quickly as possible and warn me. Meanwhile, Franco, you try to delay him even if it’s only for a few moments.’

‘I’ll tell him about my dodgy knee that’s been playing up again.’

‘How do I get my hands on a pass key for the cabins on deck seven?’ asked William.

‘No problem, sir.’ Franco took a large bunch of keys from an inside pocket, removed one with the number ‘7’ stamped on it, and handed it to William, who said, ‘I hope this won’t get you into any trouble.’

‘Not a chance,’ said Franco. ‘I had clear instructions from the commodore to give you every possible assistance, so I’m doing no more than obeying orders.’

A few moments later the first guests entered the dining room for breakfast. They stared at the chairman’s table, now roped off, while Franco led them to their usual places.

‘Got it,’ said James. ‘I’ve just worked out why you don’t need the fingerprints of anyone who was sitting on the other side of the table.’

Franco looked suitably puzzled.

‘Time for me to get moving,’ said William, as Hamish Buchanan and Dr Lockhart strolled into the dining room. William was not surprised to see them together. ‘Start work on their fingerprints immediately,’ he whispered. ‘Although time isn’t exactly on our side, don’t hurry and make sure you’re thorough,’ he added, before slipping out of the dining room.

James waited until his uncle and Dr Lockhart had sat down for breakfast before he took a seat on the other side of the table and turned his back on them. He picked up the silver hip flask and sprinkled a light layer of dusting powder over its surface.

• • •

‘Captain Neville, what a pleasant surprise to see you in Paris,’ declared an elegantly dressed, middle-aged woman who Miles had known for many years; she’d even sent flowers to his funeral. ‘Unfortunately, none of my ladies will be available until around nine o’clock this evening.’