Presently, Julie cut the plastic ties from around Alex's ankles and they went, hand-in-hand, out of the kitchen and, I presumed, up the stairs to bed. Short of shinning up a drainpipe, I would see nothing more, and in spite of being called Tom, my artificial leg didn't lend itself readily to climbing up to peep through bedroom windows.

Even then I didn't return to Ian's car and go home. Instead, I went back down the side of the house and out into Bush Close, to where Julie had parked the white BMW. It was some way down the road, well beyond the glow from the streetlight outside number twelve. I tried the doors, but she had locked them, so I sat down on the pavement, leaned up against the passenger door and waited.

I was getting quite used to waiting, and thinking.

Alex Reece clearly received more than an average bonus after being away for five days in Gibraltar, and I was just beginning to think that Julie was staying for the whole night when, about an hour after I left, I saw her coming towards me through the pool of light produced by the solitary streetlamp.

I pulled myself to my feet using the car's door handle but I remained crouched down below the window level so Julie couldn't see me as she walked along the road. When she was about ten yards away, she pushed the remote unlock button on her key and the indicator lights flashed once in response. As she opened the driver's door to get in, I opened the passenger one to do likewise, so we ended up sitting down side by side with both doors slamming shut in unison.

Startled, she immediately tried to open the door again, but I grabbed her arm on the steering wheel.

"Don't," I said in my voice-of-command. "Just drive."

"Where to?" she said.

"Anywhere," I said with authority. "Now. Drive out of this road."

Julie started the car and reversed it into one of the driveways to turn around. In truth, it was not the best-performed driving-test maneuver, and there would probably be BMW tire marks on the front lawn of number eight in the morning, but at least she didn't hit anything, and I wasn't an examiner.

She pulled out into Water Lane and turned right towards Newbury, towards home. We went a few hundred yards in silence.

"OK," I said. "Pull over here."

She stopped the car at the side of the road.

"What do you want?" she said, rather forlornly.

"Just a little more help," I said.

"Can't you just leave us alone?"

"But why should I?" I exclaimed. "My mother has paid you more than sixty thousand pounds over the past seven months, and I think that entitles me to demand something from you."

"But Alex told you," she said. "You can't have it back. We've spent it."

"On what?" I asked.

She looked across at me. "What do you mean 'on what'?"

"What have you spent my mother's money on?"

"You mean you don't know?"

"No. How could I?"

She laughed. "Coke, of course. Lots of lovely coke."

I didn't think she meant Coca-Cola.

"And bottles of bubbly. Only the best, you know. Cases and cases of lovely Dom." She laughed again.

I realized that she must have been sampling one or the other during the past hour with Alex. It was not only fear that had caused her to drive on the grass. I couldn't smell alcohol on her breath, so it had to have been the coke.

"Does Ewen know you take cocaine?" I asked.

"Don't be fucking stupid," she said. "Ewen wouldn't know a line of coke if it ran up his nose. If it hasn't got four legs and a mane, Ewen couldn't care less. I think he'd much rather screw the bloody horses than me."

"So what is Jackson Warren and Peter Garraway's little tax fiddle?"

"Eh?"

"What is Jackson and Peter's tax fiddle?" I asked again.

"You mean their VAT fiddle?" she asked.

"Yes," I said excitedly. I waited in silence.

She paused for a bit, but eventually she started. "Did you know that racehorse owners can recover the VAT on training fees?"

"My mother said something about it," I said.

"And on their other costs as well, those they attribute to their racing business, like transport and telephone charges and vet's fees. They can even recover the VAT they have to pay when they buy the horses in the first place."

The VAT rate was at nearly twenty percent. That was a lot of tax to recover on expensive horseflesh.

"So what's the fiddle?" I asked.

"What makes you think I'd ever tell you?" she said, turning in the car towards me.

"So you do know, then?" I asked.

"I might," she said arrogantly.

"I'll delete the pictures if you tell me."

Even in her cocaine-induced state, she knew that the pictures were the key.

"How can I trust you?"

"I'm an officer in the British Army," I said, rather pompously. "My word is my bond."

"Do you promise?" she said.

"I promise," I said formally, holding up my right hand. Yet another of those promises I might keep.

She paused a while longer before starting again.

"Garraway lives in Gibraltar, and he's not registered for VAT in the UK. He actually could be, but he's obsessive about not having anything to do with the tax people here because he's a tax exile. He only lives in Gibraltar to avoid paying tax. Hates the place, really." She paused.

"So?" I said, prompting her to continue.

"So all Peter Garraway's horses are officially owned by Jackson Warren. Jackson pays the training fees and all the other bills, and then he claims back the VAT. He even buys the horses for Garraway in the first place and gets the VAT back on that too. He uses a company called Budsam Ltd."

"So why is that a fiddle?" I asked. "If Jackson buys them and pays the fees, then he is the owner, not Garraway."

"Yes," she said, "but Peter Garraway pays Jackson back for all the costs."

"Doesn't that show up in Jackson's accounts or those of the company?"

"No." She smiled. "That's the clever bit. Peter pays Jackson into an offshore account in Gibraltar that Jackson doesn't declare to the Revenue. Alex says it's very clever because Jackson gets his money offshore without ever having to transfer anything from a UK bank, which would be required by law to tell the tax people about it."

"How many horses does Peter Garraway own in this way?" I asked.

"Masses. He has ten or twelve with us and loads more with other trainers."

"But don't they pay for themselves with the prize money?"

"No, of course not," she said. "Most horses don't make in prize money anything like what they cost to keep, especially not jumpers. Far from it. Not unless you count the betting winnings, and Garraway gets to keep those himself."

"So why doesn't Peter Garraway register himself as an owner in the UK for the VAT scheme?"

"I told you," she said. "He's paranoid about the British tax people. They've been trying forever to get him for tax evasion. He's obsessive about the number of days he stays here, and he and his wife even travel on separate planes so they won't both be killed in a crash and his family get done here for inheritance tax. There's no way he'll register. Alex thinks it's stupid. He told them it would solve the problem of the VAT without any risk, but Garraway won't listen."

I listened, all right.

Wasn't it Archimedes who claimed that if you gave him a lever long enough, he could lift the world?

I listened to Julie with mounting glee. Perhaps now I had a lever long enough to pry my mother's money back from under the Rock of Gibraltar.

All I had to do was work out on whom to apply it, and when.