He laughed a dead laugh and nodded at the desk sergeant, who came to life and handed us each our swipe card passes. We signed for them on a pad. DS Rich coughed. 'OK. Follow me. I'll show you to the MIT suite.'

'We were waiting for DCI George.'

He stopped and looked at us quizzically. 'DCI George is running late. I'll show you in.'

The enquiry centre was a small-to-middling room like a college classroom on the second floor. Tables and desks were arranged in a square, crammed with computer terminals, screens and phones, and at the end, a couple of whiteboards waited. The windows were either tinted or hadn't been cleaned for some time, I couldn't tell.

We sat on one of the tables and tried to look inconspicuous. Lennie bustled in from the hall.

'Alright. I'm DCI Lennie George lately of SCD7 as you know, and I'm Senior Investigating Officer for this enquiry. We've got a lot to get through so let's get started. Most of you know each other by association or reputation, those of you that don't I'll effect the introductions now. Since the LSD fiasco, a lot of responsibility has devolved to staff at our level. Well, it's had to, as most of our Police Superintendents are out of action. SCD1 lost its whole top tier that night and we've had to step up quite rapidly...'

He coughed and nodded in our direction. 'Those two foxy-looking characters at the back are our guests from the Ministry of Defence. Don't complain, they're attached. They'll introduce themselves in a minute.'

Silence.

'And now Riz will give us a little heads-up on MOD's input to this.' Lennie nodded at me. The team was gazing at me with a mixture of curiosity and flat indifference. It was difficult to gauge their mood. So. I was going to have to explain who I was, what KTS was, why my wife and I were carrying sidearms, and on top of that why they had to look forward to a gang of lunatic Muslim girls on their patch.

Wing it, Riz, I told myself.

I took centre stage by the main whiteboard and picked up the nearest Magic Marker. 'Hello. I'm Riz,' I began as I jotted mine and Bang-Bang's names and mobile numbers on the top left of the whiteboard, 'and I'm from a branch of the Ministry of Defence. This is my other half Bang-Bang, er, Holly, and she's also MOD, Military Stabilisation Support Group, MSSG for short.'

Bang-B-ang waved from the desk she was sitting on and snapped gum blankly as she swung her white go-go boots. I carried on. 'The Home Secretary has attached us to this enquiry due to several unusual aspects that she feels need our input.'

Silence. Keep digging mate, I thought. 'OK. The nature of mine and Holly's work for the MOD means we both carry firearms most of the time and are authorised to do so. Yes, we're Muslim AFO's, please don't let that alarm you.'

The ghost of a chuckle. That was better.

'To be honest, guys, I think the Home Office stuck us both in this one because we're Muslims.'

Laughter. The tension receded.

'More seriously OK me and Holly both have experience in tracking jihadis, terrorists of all stripes. It's not like we can see inside the mind of a serial killer, but... manhunting we can do. We won't get in the way though, we'll be in the corner, here.'

The mood was much lighter. I hadn't really wanted to tell them that between us we'd killed near-on thirty, forty... who was counting? And how did I feel about that? I decided to stop beating myself up as I was sure there were plenty of ex-squaddies in the building.

Suddenly Lynne spoke up and nodded her chin at Bang-Bang. 'Holly, hi. Didn't I read your obituary last September?'

Bang-Bang eased herself off the desk she was perched on and replied. 'Wasn't an obituary as such, just a mentioned-in-dispatches. I went away for a while. And then dipstick got me back!' she grinned. Lynne looked nonplussed. Heh welcome to our world, I thought.

And then Lynne sparked up again. 'You also both got Queen's Gallantry Medals, I recall.'

Bang-Bang and I glanced at each other. Oh, we'd have to watch this one. She didn't miss a trick. I replied. 'Yeah. All four of us did. But some deserved it more. Like those who died that day.'

Another silence. I waited a while and carried on.

'Lastly. We may be liaising with other members of MSSG Blackeyes locally to get tasks done. They're slightly unusual girls, but don't let that phase you either. Any questions.'

Didn't look like it. Lennie stood and swept his arm across the room. 'OK this is for your and Bang-Bang's benefit. I'll now give you a precis of what a real Murder Investigation Team does and how. First things you need to take on board are one, the computer systems, and two, the sheer amount of paperwork. Not to mention the media, because I'm also the poor bastard that has to go on Crimewatch in a week's time.'

'Crimewatch? That any good?'

'Oh yeah. It helps a lot. we get a surge of phonecalls during and after any show. Especially from prisoners. Prisoners love it.'

We laughed.

But Lennie wasn't laughing now. He was looking very grim. 'In addition, I've undertaken to deliver any future death messages myself, to spare the rest of the team. Normally the FLO would do it but I'm taking the weight off. She's dealt with enough.'

'Follow me round.' Lennie was like a conductor. We'd taken over the conference room of the station. Techies were still laying wires. 'OK. First thing you have to know is that unlike Inspector Morse, it's not all down to one detective to solve the dastardly crime. There's me, the SIO, and then I have an office manager as admin. In this case it's DI Greg Rich.'

DI Greg Rich looked at us then looked away. Lennie continued. 'Because of the workload on this enquiry, we also have DS Lynne Cammack as assistant office manager. I asked for her specially as she worked on Operation Yeaddiss, the Levi Bellfield enquiry. She's brought her notes from that and they'll be available on the office network.'

She shook our hands. 'Hello Riz, hello Holly. My number will be on the whiteboard.'

'OK, now under us, we have, the MIT, the murder team,' He waved his hand expansively again... 'who you've just spoken to. Ten to twelve people from CID and also civilian support staff typists, indexers, analysts for the I2 and Xanalys... right. Everything, and I mean everything, is dictated by HOLMES 2. It sends out what we call actions, and every action has a number.'

We'd stopped at the first open office. 'Say hello to the intelligence cell...' they waved; 'the exhibits officer, the FLO Family Liaison Officer... right, where were we?'

We'd stopped at the int cell. 'Next offices this is the CCTV viewing suite...' two cops gazed back like owlets; 'then the Detective Sergeants' office, then the staff...' A gaggle of civilian staff waved cheerily, 'then my cubbyhole, and right here is the evidence-storage room. And now we've run out of room. Come and look at the office network.' This software I knew. Industry standard, clunky but well-used. I2.

Bang-Bang was gazing curiously at a PC terminal like an archaeologist staring at an Anglo-Saxon burial mound. They still ran Windows 2000 and NT here. I supposed that Senior Management on the top floor got first dibs on all the new hardware. Bang-Bang had picked up a desktop mouse and was rolling the ball on it. She looked nonplussed.

'So, these flag up actions against a nominal. In this case, Nominal 1 could be a victim, and nominal 2 could be suspect. You with me?'

We nodded. We were with him. 'No room for error. Then a printout is made. Action 1 for detective one contact nominal 3, get a statement. Back into the system, and it's typed.'

'Then...' he pointed at an office over the way 'Every morning of the enquiry, the SIO that's me meets the guvnor in this case that's DCI Terry Lanehan, and we all have a conflab. And on it goes. And, finally ' he jerked a thumb in the direction of an A4 laminated sheet with a sheet of paper covering it, hanging innocuously on the wall; 'that, is the Word Of The Day.'

Bang-Bang looked interested. 'Word Of The Day?'

'The very same. That's the code word that has to be used when any of us request a check on the Police National Computer. The word is changed daily by the PNC bureau. You're not going to be able to get any check done without quoting that word. It's kept covered in case unauthorised persons come into the office. And you, Holly, because you're new, have the honour of picking today's word.' He handed her a Pentel marker.

She grinned and went to the wall, lifted the sheet of paper and scribbled something. She returned with an even bigger grin and handed his marker back.

He looked at her. 'OK, I'll bite. What's today's word?'

'Fifi, of course.'

'Stranger murders. Stranger murders... the hardest murders to solve, and the most expensive. This enquiry will probably cost 2 million when it's finished. With enough staff and enough time, we'll find this bastard. The only problem is we don't have enough staff. Or enough time.'

'Eight days.'

'Yeah. Eight days. Not enough.' Lennie indicated a stack of forms and witness statements. 'The thing you never see in the films.'

I looked around. The terrain was vaguely familiar from my time with the Snowdrops and the MOD. Stacks of files. Printers. Personal radio chargers sitting on the desks, some empty, some with batteries in charge. A large Hitachi television in the corner for screening CCTV. The rack for the team's stab vests, and next to it on the wall, a computer-generated timeline chart, showing the suspects' and two victims' movements. The paper chart was already stretching back towards the doors into the office.

Bang-Bang blew some gum. Lennie carried on. He seemed to be talking to himself, rather than us, his new audience. We watched. 'The other thing they always get wrong are the interviews. A row? I wish. Ninety percent of serious crims say no comment all the way through.

'And that's enough. We'll train one of you up on HOLMES 2, and the rest of us will do police stuff. We'll be meeting daily, so you can liaise with the Intelligence Cell.'

He looked at us. 'Any questions?' We had none.

'OK last thing. We need to pick a name for this operation from the approved list.'

He nodded at a desk phone. The phone was sitting on what was known as the Force Directory. This held every police-related number in Britain. 'Riz. 020 7230 1212 for New Scotland Yard; ring them and ask for Ops. They'll ask you what type of operation it is and then they'll pick a name for you from the relevant list. After you.'

OK, so I didn't need the Directory. I dialled the number and got through. Bang-Bang and Lennie chatted and compared war stories while I got put through various offices and waiting lists. Finally I had it. I replaced the receiver. They looked at me, waiting.

'It's Operation SALEM.'

Lennie nodded. 'OK. We can get started. I suppose I'd better show you the murder scenes, then.'

The words on the wall read "Jesus says, Come unto me and I will give you rest". Bethnal Green Mission Church and bookshop overlooked Paradise Gardens and a crime scene.

'She crawled to... there.' Lennie pointed into the mud and the scrubby bushes. 'We didn't put the two together until we looked at the knife wounds. Thought it might have been her pimp or a customer.'

'Did she have a pimp?'

'No.'

'Customers...'

'Well. We'll come back to that. We've also got one Misper from a few weeks back.'

'Sorry a what?'

'A Missing Person. We're waiting for something to turn up but we fear the worst as she's also a local Tom. Her name is Helen Farmer.'

'So that's three potential murders.'

Lennie looked out across the main road, back across the park to the police station. 'Yeah. One more for the timeline.'

I followed his gaze and suddenly realised how close under their noses this had all been. Literally, within eyesight.

He turned back to me. 'We're keeping some of his M.O. from the media.' I nodded. Lennie looked like he was weighing up whether to continue. I waited.

'Riz, wanna know what I think? And this is off-base, since HOLMES doesn't let us have hunches anymore.'

'Go on.'

'I think our suspect is imitating what he thinks the Ripper was. You get me?'

'Ah. All that Freemasons stuff?'

'Yeah. I reckon we should be looking for a local conspiracy buff.' I looked around the park. It had been a bit optimistic of the council to call this a park; it was more like a large garden. It was also the perfect spot for a murder.

Low railings. The railway arches. The throb and clatter of construction work. I couldn't see any cameras pointed into the gardens. I looked up at the houses and the church building windows that overlooked us. 'Asked them?'

'All of them. It was late, rainy, dark, and no-one saw shit.'

'Prints in the mud?'

'Yep. One. A new Reebok DMX Ride Cruiser, size ten.'

We stepped back onto the pavement and Lennie indicated cameras. 'A couple over by the Museum Of Childhood. One on the wall of the petrol station there. All the footage is being looked at right now.'

We walked on. Lennie was on a roll, by the looks of it. Expansive. He gestured northwards. 'Tottenham was my old patch when I was a woodentop. Rough old manor then, even rougher now. I was a police cadet when they still had them. The same month I joined the cadets, the riots kicked off and they killed PC Blakelock. No going back from then on. My first night as a probationer, they sent me out to wave down traffic on the one-way system but they put dead batteries in my torch. Apparently it's so you learn that you piss them off anyway as a PC, regardless of your skin colour.' We continued walking.

'Did you know that serial killing in Britain peaked in 1986?'

'No, Lennie, I didn't know that.'

'It did. The golden age of serial murder. OK there are four types of serial killer, Riz. Visionary, Mission, Hedonistic, and Power/Control.'

'Right. Which one d'you think our one is?'

He stopped. 'Mission. Just my ha' penny worth.'

'Not pleasure?'

'Nah. Anyway I'm not allowed to have hunches or mad deductive leaps. That's your job.'

Lennie carried on. 'I was Borough Crime Squad for five years, then undercover SO10, then Sweeney. Loved every minute of it.'

I knew all this of course. I'd read our TANGENT file on him. He hadn't mentioned the Queen's Police Medal for gallantry he'd been awarded, for some of the scariest shit I'd ever read during his tenure in SO10. He also hadn't mentioned his winning the Lafone Cup, the Met's boxing trophy, when he was still uniform at Tottenham. Good bloke to have in the trench next to you, I thought.

Our travels took us to the end of Bethnal Green Road. The end was still cordoned off. 'They reckon the Infidels or Combat 18 did it' said Lennie.

'Yes. They reckon.'

Lennie raised an eyebrow at me. 'Come on. Let's get a pint. You can tell me about what happened in Birmingham.'

Lennie and I walked away from the taped-off rubble, back towards the tube station. Lennie lit two cigarettes, handed one to me, took a long drag on his, and spoke.

'This wannabe Ripper, Riz it's someone who's bought into all that Stephen Knight flim-flam.'

'You reckon?'

'You and me both know the original Ripper was most likely a local man, with local knowledge. Not Prince Bertie, or Ebeneezer Goode in his top hat.'

I laughed. 'OK. That's true. But our perp?'

'Yeah. Our perp probably loves all that stuff. I'm William Gull! I'm Ed Sickert! I'm a giant vulture!'

By now I was laughing even harder. 'Lennie. You and I need a beer. Follow me; we're going to the Salmon and Ball before we start thinking too hard.'

'I hear you. But listen. That's how we might catch him. By what he thinks he should be doing. Another thing to remember, Riz serial murderers don't pick their victims at random. There is always something in the victim that speaks to them. If we can work out what that is, we're partway there.'

'Kelly Bowen was a prostitute, Fifi was a burlesque performer. Our Misper now known to be Helen Farmer was also a prostitute. To the murderer maybe they were all "women of easy virtue"?'