But credit to Tina Boyd, she didn't turn round and leave, even though I think I would have done. Instead she asked to see Jenny's apartment.

Gentleman didn't look too happy. He said he wasn't authorized, but Tina was insistent, so he located the keys and took us up in the lift.

As he unlocked Jenny's front door I scanned the woodwork for signs of forced entry but there wasn't a single scratch. I wondered how the hell the two kidnappers had got in. Jenny hadn't let them in. She'd been in the bedroom.

So, the chances were they'd also had a key.

I knew what the inside of the apartment was going to look like before Gentleman led us inside, and my suspicions were immediately confirmed. The front room was immaculate. The coffee table I'd clipped while running away was set at exactly the right angle between the two sofas.

Gentleman and Tina both looked at me expectantly. Unsure what to say, I walked past them and into the bedroom.

The bed was made. There was even a cuddly teddy bear with a sky-blue bow sitting perfectly symmetrically between the two sets of puffed-out pillows. The bathroom door was shut. There was no sign of the clothes Jenny had been wearing nor, more worryingly, my jacket. In fact, nothing was out of place. The room was so damn tidy it could have been part of a show home.

I flung open the bathroom door. It was perfect in there, too. No sign of any bloodstains from where I'd clouted the Irish guy with the soap dish. What I did notice, however, was that it smelled of disinfectant in a way it hadn't done earlier.

'Someone's cleaned this place up,' I said firmly, turning round.

'I can see that,' said Tina, coming into the room behind me. 'It looks great. But let me tell you something, Mr Fallon. In my experience, criminals never like to hang around after they've committed their crime. If these two men kidnapped Miss Brakspear, as you say, then it's extremely unlikely that they would have taken the time to make the bed and give the place a spring clean afterwards.'

'I know that,' I said, feeling like I was going mad. 'But that's exactly what happened. I promise you that. I'm not making it up.'

For several seconds, Tina didn't say anything. Gentleman appeared in the doorway of the bathroom. He was wearing an expression that was part way between irritation at being dragged all the way up here and the kind of patronizing pity usually reserved for the mentally ill.

What was worse was that in his shoes I'd have felt exactly the same.

Tina asked him if all the apartments on this floor were occupied.

'I'd have to check,' he answered, 'but I think Jenny might have been the only one living on this floor. What with the credit crunch, they've only sold about half the units in the building. Maybe not even that.'

Christ, that was all I needed.

We went back outside, and even though it was past three in the morning Tina knocked on the doors of the floor's other three apartments. No one answered.

I felt embarrassed and confused. Those events just hours earlier had happened – the fact that my jacket was missing was enough to prove that – but there was absolutely nothing I could do about it.

Tina got Gentleman to copy the footage from the CCTV camera on to a USB stick she was carrying and thanked him for his time. When we were outside, she told me she'd file a report and make some enquiries, but there was little enthusiasm in her tone.

'Someone's covering for these guys,' I persisted, trying to keep the desperation out of my voice. 'I swear it. That's why the camera for the underground car park wasn't working. Why there was no sign of forced entry. And why the place was cleaned up. I was there tonight and I know exactly what I saw. I bet if you check that footage through carefully enough, you'll see that it's been tampered with.'

Tina put up a hand to stop me. 'I'm sorry, Mr Fallon, but criminal conspiracies are a lot rarer than most of us like to think. Criminals just don't tend to be that clever. If two men did kidnap Miss Brakspear, it's highly unlikely that they were in cahoots with the door staff because the more people there are who know about something like this, the harder it is to keep it secret. Even you've admitted that Jenny's an ordinary girl with an ordinary job, and was acting perfectly normally when you met her earlier, so it's highly unlikely she's a victim of some kind of conspiracy. What I want you to do is to keep calm, try not to read too much into everything, and leave the investigating to me.'

'I bet if you check passenger lists for all flights to Barbados out of London Jenny Brakspear's name won't appear on them.'

'Mr Fallon, please.'

I wanted to keep trying to convince her that I was telling the truth, but I could see it wouldn't work. Instead, I asked her what she planned to do.

'I'll contact Jenny's place of work, and I'll contact her family to find out if they can shed any light on things. And when I've done that I'll be in a better position to decide what to do next.' She pulled out her car keys. 'You said you didn't have any money, didn't you?'

'That's right. My wallet was in my jacket.'

'Where do you live?'

'Colindale.'

'Do you want a lift home?'

I nodded, thankful at least for this kindness. 'Please.'

We drove back in silence. For a while I shut my eyes, but I didn't sleep. It was just easier than talking to DS Boyd. I knew she didn't believe me, and I could understand her scepticism, but it was an awful feeling to have witnessed a violent crime and know that a young woman's life was in danger yet have no one take you seriously.

Traffic on the road was sparse and it was barely twenty minutes later when Tina turned into my street.

'Whereabouts is your house?'

'Anywhere round here's fine,' I said, not wanting her to see my crappy little pad after Jenny's flashy apartment.

She pulled in a few doors down from Ramon's place and yawned. 'Get some sleep, Mr Fallon. And when you get up tomorrow have a good long shower. You're not smelling your best.'

I nodded. 'Thanks for the lift, and please, don't give up on this. There's a young woman missing. If we don't do something…'

'I'll make enquiries, I promise.'

'Can I take your number? Please. Just in case I think of anything else.'

She didn't look too happy but produced a business card from her handbag and handed it to me. 'I don't want you to take this as an excuse to keep calling me, Mr Fallon, because it won't help me locate Jenny. And I'm off duty in a couple of hours and I'll be sleeping. Understand?'

'Sure, thanks.'

Reluctantly, I got out of the car and stood in the darkness. DS Boyd pulled away with a small wave and her car quickly disappeared down the street, leaving me alone.

The night was dark and cool, and for a few minutes I stayed where I was. I thought about going to Ramon's place and asking if I could stay there but there were no lights on in his flat and I really didn't want to have to recount what had happened to anyone else and endure their sceptical stares. So I slowly headed down the street.

Home for me was a rented one-bed ground-floor flat in one of the 1950s terraced houses that lined both sides of the road. I'd been there over a year but had never really got used to it. It was small and characterless, and I'd spent far too many lonely hours in it.

Approaching the front door now, I felt the tension rising in me, knowing it was possible that Jenny's kidnappers had already used the information in my wallet to find out where I lived. I looked over my shoulder but the street was silent. I checked the locks on the door but they were intact. Taking a deep breath, I opened the door and stepped inside.

That night at least there was no one waiting for me. I switched on the light and went through to the kitchen, where I poured myself a glass of water and drank it down in one. For the first time that night I noticed how awful I smelled and it amazed me that Tina had volunteered to drive me home. Her car must have reeked, yet she hadn't made a fuss. She struck me as a good-hearted person, even though she had an impressive line in cutting looks, and a good detective as well. There was an air of quiet confidence about her which I liked, and I really hoped she'd do something with this investigation.