I shook my head. 'From what I can gather they were trying to get her out of the apartment as fast as possible.'

'OK,' she said, writing something down in the notebook. 'And what's Jenny's last name?'

My mind suddenly went blank. I'd only ever known her as Jenny, although I had definitely been told her last name before. I racked my brains. 'It's…Brakestone, Brakeslip, something like that. No, Brakspear. It's definitely Brakspear.'

'You're sure about that?'

I nodded, way too vigorously, conscious of how unconvincing this must sound to a police officer. 'Yeah, I'm sure.'

'And you met her in a bar tonight? I'm assuming you'd had a few drinks?'

'I'd had a few, yes, but I knew what I was doing.'

'And you say Jenny's a friend of yours? But one whose last name you don't remember?'

'I don't know her that well, OK?'

DS Boyd shot me a hard look, the kind that told me in no uncertain terms to remember who I was dealing with. 'Listen, Mr Fallon, I'm just trying to establish the facts. So how exactly do you know her?'

'She went out with a friend of mine for a while.'

'And your friend's name is?'

'Dominic Moynihan.'

She wrote down Dom's contact details, then asked me when the two of them had split up.

'A while back. Maybe a year.' I thought about adding that he'd been in touch with her recently about getting back together but stopped myself, knowing that it wouldn't make me look good.

'What do you do for a living, Mr Fallon?'

'I'm a writer.' Usually I loved to say that to people, but now it sounded fatuous, and tinged with an air of unreliability.

'And what do you write about?'

'Does it matter? I'm trying to report a kidnap here. A young woman's been abducted and we need to find her.'

DS Boyd gave me another of those looks. 'I'm just trying to find out some background. It'll help us in our search.'

'I write crime,' I answered wearily. 'True crime.'

'And does it involve a kidnap?'

'No it doesn't. Jesus Christ! What the hell do I have to do to convince you I'm telling the truth? Do you think I want to be sitting here in the middle of the night talking to people who'd far rather I just went away?'

I fell silent, staring at her. Feeling at the end of my tether.

DS Boyd rested her hands carefully on the desk and looked at me closely. She had very dark eyes but it was difficult to tell whether they were brown or blue. 'OK, Mr Fallon,' she said, 'let me level with you. It may surprise you to learn that we get a lot of people coming in here reporting crimes that haven't actually happened, particularly when they've been drinking. We're also very busy dealing with the many crimes that do happen, so I have to ask a lot of questions before I'm in a position to judge what to do. Now I've heard what you've got to say and I'm satisfied that you genuinely believe an incident's happened-'

'It has. I promise you.'

'Then I'm going to give you the benefit of the doubt.' She stood up abruptly.

'Where are you going?'

'To the scene of the crime.' She gestured for me to follow her. 'I'm assuming you remember where that is?'

'Kidnapping's nothing like as rare as people think,' said Tina Boyd as we approached the double doors at the front of Jenny's apartment block, 'but it's almost always drugs-related. People getting held to ransom by dealers over unpaid debts, that sort of thing. Could Jenny have been involved in the drugs trade, do you think?'

I couldn't honestly say for certain, but Dom had never mentioned anything about it, and he'd been anti-drugs since a friend of his had OD'd on a mix of coke and ecstasy back at uni, so I didn't think so. 'She's just a normal girl, you know,' I answered wearily.

'That's what I can't understand,' she mused, pressing her warrant card against the glass so that the doorman could see it. It was the same guy as earlier – grey-haired, middle-aged, ordinary looking. He buzzed us in.

I felt strangely sheepish as I followed Tina over to the front desk. She introduced us both and said that I'd been in the building about three hours earlier and had witnessed a possible abduction.

The doorman fixed me with a bemused expression. 'Really? Who was abducted then?'

'A Miss Jenny Brakspear. Apparently she lives on the ninth floor.'

He frowned. 'Blonde Jenny?'

'That's her,' I said.

He looked puzzled. 'That's weird. I haven't even seen her tonight. I thought she'd gone on holiday.'

'Hold on,' I said, unable to believe what I was hearing. 'You did see her. She called out to you. Your name's John, right?'

'Yeah, it's John, but I still didn't see her.'

'John what?' asked Tina.

'Gentleman,' he answered, 'and I'm telling you I didn't see her tonight.'

Tina wrote down his name in her notebook. Not that John Gentleman was one you were likely to forget. I couldn't believe the guy was lying.

'What's supposed to have happened then?' he asked Tina, giving me a distasteful look.

'We can't divulge any details at the moment, sir,' she answered smoothly. 'I'm assuming you've got CCTV cameras in this building?'

Gentleman nodded. 'We've got two. One's at the back, at the entrance to the underground car park, and there's another above the front doors where you've just come in. The one at the back's been on the blink for the last few days. We've got an engineer booked in for tomorrow. But the front one's working all right.'

'Mr Fallon says that he came in here at approximately midnight. Do you mind if we take a look at the footage for about fifteen minutes either side?'

'Sure,' said Gentleman, double-clicking on a mouse under the desk and turning round the PC monitor so we could see what was happening. 'We use DVR filming technology in the cameras so it records straight to the computer's hard drive. It means we can store the film indefinitely.' He double-clicked again and a close-up aerial view of the area just outside the double doors appeared. He fast-forwarded through it quickly until the time in the bottom left-hand corner said 23.30. Next to it was Sunday's date. 'Right, I'm slowing down the search now so we're moving through the footage at sixteen times normal speed. Just let me know when you want me to stop.'

We watched in silence. For most of the time the area was empty. Occasionally, though, people appeared, and Gentleman slowed down the footage so we could get a look at them. He seemed very keen to be as cooperative as possible.

The time in the bottom corner of the screen hit 00.00 and Monday's date appeared. Gentleman kept searching. A handful of other people appeared, but not Jenny and me. It hit 00.15. Gentleman looked at Tina expectantly, and she looked at me.

'You said midnight didn't you, Mr Fallon?'

'It might have been a bit later,' I muttered, even though I knew it hadn't been.

I watched as the time moved inexorably towards 00.30.

'This is bullshit,' I said eventually. 'This film's been tampered with. I was here tonight. I can describe Jenny's apartment if you want me to.' I ran a hand across my forehead, feeling the exhaustion taking hold, trying to get a grip on what the hell was happening.

'Look, mate,' said Gentleman, 'I've been here all night and I haven't seen you, I haven't seen Jenny, and I haven't tampered with this. Nor's anyone else.'

I turned to Tina. Her expression was impassive. It was impossible to tell what she was thinking.

'When was the last time you saw Miss Brakspear?' she asked the doorman.

'Yesterday, I think. She told me she was going on holiday.'

'Where?'

' Barbados. She's a bit of a world traveller, Jenny. I thought she said she was going tonight, but it might have been tomorrow.' He shrugged, his casual demeanour suggesting that my story was no longer even worth attempting to take seriously.