Brownlow was forced to admit that he had a point. ‘Neither of those would be quiet, though. The other people in the cabin would still hear it being fired.’
‘They might,’ agreed Gold. ‘But they wouldn’t think anything of it… if it were a sound they had already heard before!’ On their confusion, he went on: ‘Put yourself aboard that plane—’
‘I wish I got paid that much.’
‘Then you’re in the wrong line of work, I’m afraid. But imagine yourself in the first class cabin. You have your own personal suite, with a number of lovely young flight attendants at your beck and call. The food and drink is all of the highest quality and has already been paid for in the price of your ticket, so is effectively free. Now, what is the first thing you’re offered once you’re settled in your suite?’
‘A drink,’ said Meadows after a moment.
‘Precisely! What drink? Remember, you’re in first class.’
‘Champagne?’
Gold jabbed at the air with his index finger. ‘Exactly! Champagne. Every passenger in first class is plied with as much champagne as they can drink, within reason — in the case of this particular Air Thailand flight, 1996 Dom Pérignon. An excellent vintage, although at over two hundred and fifty pounds a bottle you’d certainly hope so.’
Meadows looked appalled. ‘Two hundred and fifty quid a bottle?’
‘Oh, that’s nothing. I have several vintages that cost more than that in my stock. And you could spend over six thousand pounds on some Doms — though admittedly the bottles are coated in white gold. Which is one way to encourage recycling.’
Brownlow had already followed Gold’s line of reasoning to its conclusion, and was distinctly dubious about where it led. ‘So you’re saying that the murder weapon… was a champagne bottle?’
Gold seemed mildly put out, yet also pleased, that the detective had reached the answer so quickly. ‘I am indeed. If there’s one loud and sudden sound that you can expect to pass completely unnoticed in the first-class cabin of an airliner, it’s the pop of a champagne cork. Twelve people, on a twelve-hour flight, will get through a lot of bubbly.’
‘We noticed,’ said Meadows, remembering the line of empty bottles. ‘But — are you seriously suggesting that Perch was killed by a champagne cork with a bullet in it? That’s ridiculous!’
Gold merely shrugged and crossed the room to the bar, opening a fridge behind it and taking out a bottle of champagne. He returned to the sofa and stood facing his guests as he peeled away the foil. ‘Don’t worry, it’s not vintage. I reserve those for special occasions.’ He began to unfasten the wire cage containing the cork.
‘Bit early for that, isn’t it?’ Brownlow said.
‘It’s never too early for champagne. I’d offer you some, but since you’re both on duty and have the unmistakable disdainful expression of Puritans I know you wouldn’t accept.’ He dropped the cage onto the coffee table with a clink and placed one thumb behind the head of the cork… then carefully tipped the bottle downwards, pointing it at Meadows.
She shifted uncomfortably. ‘What are you doing?’
‘Proving a point.’ His knuckle whitened as he applied more pressure.
‘Well, point it somewhere else!’
‘Why? It can’t possibly kill you; you said so yourself.’
‘Maybe not, but it’ll still hurt!’
Gold smiled. ‘Precisely. It will hurt.’ To her relief, he turned away and put down the bottle. ‘Now, the pressure inside a champagne bottle is around ninety pounds per square inch, or roughly three atmospheres. Which, as you say, is more than enough to hurt if the cork hits you. So what would happen if you increased that pressure?’
‘It’d hurt more?’ suggested Brownlow, a little facetiously.
‘Actually, no,’ said Gold, shaking his head. ‘The bottle would explode, because it’s not designed to withstand much more than it needs to. Which brings me on to my third deduction.’
‘The acrylic flakes?’
‘Ah, so it was acrylic! I thought that seemed more likely.’
Brownlow was irked that Gold had successfully pried information about the case out of him, but Meadows had an objection of her own. ‘So when exactly did you find the time to work all this out?’ A glance towards the hall after the departed flight attendants. ‘It looked like you’d been busy with something else last night.’
‘Oh, the girls were exhausted and fell asleep quite early — midnight or so. That gave me plenty of time to mull matters over. I’m a light sleeper, and I’m never far from a laptop or iPad. I did some research on ways that a bottle might be strengthened.’
‘And what did you find?’ asked Brownlow.
‘That there are numerous resins which could be poured into an empty bottle in liquid form and allowed to set, hugely increasing the bottle’s overall strength. A centrifuge could have been used to ensure an even coating, I suppose. I don’t know for sure,’ he added airily. ‘The specifics are for you to find out.’
‘I’m glad you’re leaving us something to do,’ Meadows remarked acidly.
‘Well, the police are funded by the taxpayer, and as a high-rate taxpayer I want to get my money’s-worth. Anyway, the bottle could certainly be strengthened enough to contain the sort of pressure that could fire a projectile with potentially lethal force. Then it would just be a matter of putting in a cork in the bottle.’
‘A cork would never hold that sort of pressure,’ she objected.
A patronising look. ‘This cork wouldn’t be made of wood, Detective Constable. No, it would have to be some sort of hard rubber.’
‘Or plastic,’ said Brownlow thoughtfully.
Gold raised an eyebrow. ‘Plastic? Yes, I suppose that would be better. But then, I’m not an engineer. But whatever it’s made of, it’s not just a cork — it’s a sabot.’ He caught a brief flash of puzzlement on Meadows’ face. ‘Oh, come now, Detective Constable. Surely you know what a sabot is.’
‘Of course,’ she said, unconvincingly.
‘A sabot,’ said Brownlow, covering for her, ‘is something that you put around a bullet to make sure it’s properly sealed in the gun barrel. We’re not entirely uneducated at the Met.’
‘I’m delighted to hear it,’ Gold proclaimed with a grin. ‘But the murderer put the cork in the bottle… and then put the bullet in the cork. That’s how it got through airport security undetected.’ He picked up the discarded wire cage and showed it to them. The domed cap that had covered the top of the cork was still inside. ‘A small-calibre bullet is only about half an inch long, if that — the cartridge is most of the length of the round. Put a metal cap over it, probably made of lead so the densities are the same on the x-ray, and all the scanner operator at the airport will see is what they would expect to see — a perfectly ordinary champagne bottle.’
‘But one that’s now a weapon.’
‘Exactly.’ He picked up the bottle again and pointed it at Brownlow, stepping closer. ‘So the killer brings it to Perch’s suite, takes off the cage, pushes the cork — and pop! The sabot shoots out, tearing away flakes of the acrylic lining as it goes. Its broad end bounces off Perch’s chest, but the bullet inside it has sufficient momentum to keep going and penetrate his body. Hence my fourth deduction, the bruise around the entry wound. It’s the perfect murder. A man is shot dead while surrounded by people… but all anyone hears is something they’ve heard many times during the flight. The pop of a champagne cork.’