The woman I had followed in selected a couple of sets of details, then approached the young man behind the desk that sat at an angle to the room. He looked as if he should be in a classroom swotting for his GCSEs. I know they say you should worry when the policemen start looking younger, but estate agents? She asked in a low, cultivated voice if she might arrange to view both properties. I was surprised; she was wearing a knitted Italian suit that couldn't have cost less than three hundred pounds, her shoes looked like they'd come from Bally or Ravel, the handbag was a Tula, and I'd have put money on the mac being a four hundred pound Aquascutum. Put it another way, she didn't look like a terraced house in Whalley Range was her idea of a des. res. Maybe she was looking for a nice little investment.

As I studied her, the lad behind the desk was phoning to fix her up with viewing appointments. I took in the grooming: the polished nails, the immaculately styled dark brown hair, the expert make-up that accentuated her dark eyes. I had to admire her style, even though it's one I've no desire to aspire to.

I'd stared too long, however. The woman must have felt my eyes on her, for she turned her head sharply and caught my gaze. Her eyes seemed to open wider and her eyebrows climbed. Abruptly, she turned on her heel and walked quickly out of the agency. I was gobsmacked. I didn't know her from a hole in the ground, but she clearly knew me. Or maybe I should say, she clearly knew who I was.

The lad looked up from his pad and realized his customer was halfway out of the door. 'Madam,' he wailed. 'Madam, if you'll just give me a minute…' She ignored him and kept walking without a backward glance.

'How bizarre,' I said, approaching the desk. 'Do you always have that effect on women?'

'It takes all sorts,' he said with a cynical resignation that would have been depressing in a man ten years his senior. 'At least she took the details with her. If she wants to view, she can always phone. Maybe she remembered an appointment.'

I agreed. Privately, I was dredging my memory of recent cases, trying to see if I could place the elegant brunette. I gave up after a few seconds when the lad asked if he could help me. 'I'd like to talk to whoever's in charge,' I said.

He smiled. 'Can you tell me what it's in connection with? I might be able to help.'

I took a business card out of my wallet, the one that says Mortensen and Brannigan: Security Consultants. 'I don't mean to appear rude, but it's a confidential matter,' I told him.

He looked slightly disconcerted, which made me wonder what little scam DKL were up to. He pushed his chair back and said, 'If you'd care to wait a moment?' as he reversed across the room and through a door in the far corner. He emerged less than a minute later, looking slightly shaken. 'If you'd care to go through, Mrs… Lieberman will see you now.'

I flashed him a quick, reassuring smile, then opened the door. As I entered the back office, a woman I put in her late forties rose from a typist's chair behind an L-shaped desk. On one leg of the desk, an Apple Mac stood, its monitor showing a full page mock-up of some house details. Mrs… Lieberman extended a well-manicured hand displaying a few grands' worth of gold, sapphires and diamonds. 'Miss Brannigan? I'm Rachel Lieberman. Do sit down. How may I help you?' I instantly realized who had taught the young man in the front office his style.

I gave her the once-over as I settled into a comfortable chair. Linen suit over a soft sueded silk blouse. Her brown hair, with the odd thread of silver, was swept up into a cottage loaf above a sharp-featured face that was just beginning to blur around the jawline. Her brown eyes looked shrewd, emphasized by the slight wrinkles that appeared as she studied me right back. 'It's to do with a matter I'm looking into on behalf of a client. I'm sorry to arrive without an appointment, but I was in the area, so I thought I'd drop by on the off-chance of catching you,' I started. She looked as if she didn't believe a word of it, a smile twitching at one corner of her mouth. 'I wonder if you can clear something up for me. I realise that your main office is in Warrington, but are you actually the owner of 3KL, or do you manage this branch?'

'I own the company, Miss Brannigan.' Her voice had had most of the northern accent polished off. 'I have done since my husband died three years ago. Daniel Kohn Lieberman, hence he name of the company. What, if anything, does that have to lo with your client?'

'Nothing, Mrs… Lieberman, except that I shouldn't imagine a manager would have the authority to release the information 'm after. Mind you, a mere employee probably wouldn't grasp he importance of it, either.' I tried that on for size. I hoped she was a woman who'd respond to flattery. If not, that left me with nothing but threats, and I hate to threaten anyone in daylight hours. It takes so much more energy.

'And what exactly is this information?' she asked, leaning forward in her chair and fiddling with a gold pen.

'I'd like to level with you, if I may. My company specializes n white-collar crime, and I'm investigating a serious fraud. We’re looking at a six-figure rip-off here, probably more like a trillion. I suspect that the perpetrators may be using properties in a short-term lease for their particular scheme.' Mrs… Lieberman was listening, her head cocked on one side. So far, no reaction was making it through to the surface. I soldiered on.

'One of the addresses I'm looking at was rented through your agency. What I'm trying to do here is to find a common factor.

The thing is, I'm beginning to think the renting of the houses is a key factor in the way the fraud is organized, and I hoped that if I gave you the addresses of the other houses I suspect have been involved, then you could check for me and see if they are on your books.' I paused. I wanted some feedback. I'd never have made a politician.

Mrs. Lieberman straightened up in her chair and drew her lower lip under her teeth. 'And that's all you want to know? Whether or not they're on my books?'

'Not quite all, I'm afraid. Whether they are now or have ever been on your books is the first step. Once we've established that, I want to ask you the names of the owners.'

She shook her head. 'Out of the question. I'm sure you'll appreciate that. We're looking at very confidential matters here. There are only a few agencies that specialize in rental properties in this area, and we are by far the biggest. I act as agent for almost three hundred rental properties, the bulk of them on short-term leases. So you can imagine how important it is that my clients know they can trust me. I can't possibly start giving you their names. And I can't believe you really expected me to. I'm sure you don't release information like that about your clients.'

'Touche. But surely you can tell me if a particular property is on your books? Then when you call up the details on your screen, you might notice a pattern emerging.'

'What sort of a pattern did you have in mind, Miss Brannigan?'

I sighed. That's what I don't know, Mrs… Lieberman. So far, all I have to go on is that I think most of the addresses involved in this scam have been rented. In one case that I'm sure about, I know that the couple who rented the house shared the surname of the couple who actually owned it.'

Rachel Lieberman leaned back in her chair and gave me the once-over again. I felt like a newly discovered species of plant -strange, exotic and possibly poisonous. After what seemed to me to be a very long time, she nodded to herself, as if satisfied.

'I'll tell you what I'll do, Miss Brannigan. If you give me the addresses you're interested in, I'll look through my records and see what I can come up with. Frankly, I have to say, I think it'll be a waste of time, but then I wasn't doing anything this evening anyway. I'll call you and let you know. Will Monday morning do, or would you prefer me to ring you at home over the weekend?'