pulled up in a side street in Bolton. 'What are we doing here, Brannigan?' Richard asked.

I got out of the car, and he followed. 'After that Chinese in Buxton, I thought we deserved something a bit special,' I said, turning the corner and pulling one of the double doors open. Richard followed me down a flight of stairs and into a marble foyer with a fountain filled with koi carp. They do a ten-course Imperial Banquet,' I told him as we walked into the restaurant proper.

His face lit up. His eyes even twinkled. I doubt I'd have got that strong a response if I'd jumped on one of the tables and stripped off. I gave the waiter my name and we followed obediently to a table shut off from the main body of diners by tall lacquered screens. By the table, as ordered, was an ice bucket filled with Chinese beer and a bottle of Apollinaris mineral water for me.

Times like this, I'm tempted to make you an offer you couldn't refuse,' Richard said as the waiter opened a beer.

'I don't do "married",' I reminded him. 'Married is for mugs, masochists and mothers. None of which I am.'

'Yet,' he said.

I scowled. 'Do you want to eat this meal or wear it?'

Richard held his hands up, palms towards me. 'Sorry!'

The dim sum arrived, and we both observed the requisite awed appreciation. Five seconds later, we attacked.

Through a mouthful of char siu bau, Richard said, 'So fill me in on the details. All I know is that these days, Friday nights the best place to find you is talking to a copper.'

The poor sod had finally reached me on my mobile some time after ten. I'd been sitting in an interview room at Buxton police station, going over the whole story with the local inspector plus Delia Prentice, whom I'd asked them to ring because of the fraud stuff. Just for once, I fancied having someone on my side during a police interrogation. Neither of them had been particularly amused when I broke off to answer my phone.

I'd finally got home in the small hours, posted the 'Do Not Disturb on Pain of Castration' notice on my bedroom door and slept till mid-afternoon. By then, of course, Richard was at the match. Sometimes it's like being married anyway.

'Cutting a long and boring story short,' I said, 'when I put all the computer files together, the picture emerged. You have to remember that Martin Cheetham was an expert in arranging the sale and purchase of houses. What happened was that when he acted for the buyers of a property, he just omitted to forward all the paperwork to the Land Registry.'

'Sweetheart, you might as well be talking Mandarin,' Richard said. 'Let's have it from the top. Mortgage fraud for beginners.'

I sighed. This is how to get two mortgages on one property. Mr. and Mrs. X buy a house. They go to Martin Cheetham, solicitor. The mortgage is arranged and granted. Then Cheetham should send the paperwork to the Land Registry, who issue what's called a charge certificate, which shows that there is a mortgage outstanding on the property, and who carries the mortgage.

'But Cheetham used to delay a few weeks before he sent the documentation off to the Land Registry. He would then apply for a second repayment mortgage with another lender, as if it had never been bought by Mr. and Mrs. X. According to Nell, who couldn't stop talking once her throat started working again, she used to front up with Cheetham at the mortgage interviews and pretend to be his wife. As the first charge certificate hasn't been issued yet, there is therefore no official record of it when the lender checks it out with the Land Registry, so there's no problem and the mortgage is granted. You with me so far?'

Richard nodded. 'I think so.'

I scoffed a couple of prawn wontons and some tiny spring rolls before all the dim sum disappeared down Richard's throat.

A more suspicious soul than me might wonder why it is I always seem to end up explaining the intricacies of my cases when there's food on the table.

That second lot of paperwork never goes anywhere," I said. 'It sits in a safe in Cheetham's office. It would take the building society at least a year even to notice that they hadn't received the appropriate charge certificate, never mind do anything about it. Cheetham and Lomax have meanwhile got a (say) £100,000 cheque, because the building society paid the money to Cheetham on behalf of the second, fictitious buyers. As long as the mortgage installments were made each month, there'd be no problem. No one would be any the wiser for at least a year. Multiply that by ten and a completely uncreditworthy person has a million.'

'Shit,' Richard breathed.

'Now, you can go for a short-term fraud and do a runner with the money, in which case you have the police looking for you. Or you can do what Cheetham and Lomax had been doing very successfully until a few months ago. What they did with the money was buy up derelict property. Lomax would send in his labourers and do it up, and then they'd sell at a huge profit, thus laundering the money as well. They could have carried on with this indefinitely if the bottom hadn't dropped out of the housing market, since they were paying off the bent mortgages within a year of taking them out.'

'You mean, before the lender noticed they hadn't got this charge certificate for the loan, Cheetham paid all the money back?' Richard asked.

'Correct. And in the meantime, he and Lomax had made about fifty per cent profit with the capital. It's a victimless crime. The lenders lose nothing; they don't even know anything dodgy's happened.'

Richard laughed. 'That's brilliant! And hey, they even did their own conveyancing, so they didn't have to fork out those exorbitant lawyer's fees. So why did it all come on top?'

'Like I said, the bottom dropped out of the market. Property stopped moving. They were lumbered with houses they couldn't sell. That's why they tried that hooky land scheme that caught Alexis and Chris. They were getting desperate for cash flow. So Lomax persuaded Cheetham to get a dozen new mortgages to keep them afloat. He'd no intention of ever paying a shilling on those mortgages. According to Nell, he reckoned that if they did that, they could have a million in capital. The three of them could flee the country to somewhere like Spain. Then when the market picked up, they could offload the rest of the houses and cash in on them too. We're talking twenty-seven houses, with an average value of thirty-seven thousand pounds, by the way. Which is another cool million.'

'Shit,' Richard said again. That is serious money, Brannigan. Why didn't you finish your law degree?'

I ignored him and concentrated on the aromatic crispy duck that had just arrived, piling shredded duck and spring onion on to a pancake covered in plum sauce. Some things are too important to be distracted from.

'So why did they kill Cheetham? I mean, everything seems to have been going OK. Why get rid of the only guy who knew how to work the scam?'

I fiddled with my food. 'According to Nell, that was my fault.'

'How'd she work that one out, then? Doesn't sound like she's got a degree in logic,' Richard said.

'Cheetham panicked when I started sniffing around,' I explained. Then when he was tarted up in his drag in DKL Estates and I turned up, he was convinced I was on to their major scam. So he told Lomax to warn me off. Apparently, he meant just that. Lomax or one of his labourers was supposed to threaten me in a dark alley. Instead, Lomax must have picked me up outside DKL, then followed me over to Ted's factory, and then, on the way home, he got a bit carried away, and tried to run me off Barton Bridge. He must have completely freaked out when I turned up the very next day on his home turf. Especially since he was actually with Cheetham.'

'So why kill Cheetham? Why not just finish the job they'd started on you?' he asked.

Thank you, Richard. You don't have to sound quite so eager. The reason I'm still here is that they didn't know how much I knew, or how many people knew what I knew. But the Lomaxes figured Cheetham was the weak link in the chain, the one who'd crack under pressure. They also figured that with him out of the way they could destroy the evidence and leave themselves in the clear. So Nell arranged to meet Cheetham for one of their little games sessions. Then, when she'd got him all tied up, Brian arrived and smothered him. The pair of them tipped him over the balcony, so it looked like a nasty sex game that had gone horribly wrong.'

'And I thought my ex-wife was a bitch. Jesus. What kind of a woman does that to her lover?'

'One who's more in love with money than she is with him, I guess,' I said. They thought they'd got rid of all the evidence. But neither of them knew anything about computers. They thought all the data was on the floppies.'

'And will Alexis get her money back?'

'She'll probably have to take Brian Lomax to court. But at least she knows where he's going to be for the foreseeable future. She won't have any trouble filing the papers. Her money should be safe as houses.'