'Yes.'

'That would be the Derringer.22?'

'Yes, sir.'

'And where was he carrying this back-up gun?'

Maddy faltered. 'I don't know. I mean, I'm not sure.'

'But you did see it? The second gun?'

Christ! Why was this so difficult? 'Not at first, no.'

'How do you explain that?'

'He was carrying it out of sight. Concealed.'

'But I thought he had just jumped out of bed naked,' Mills said, taking over. 'Next to naked.'

'He was wearing trousers.'

'Trousers?'

'Yes.'

'Just trousers?'

'Yes.'

'So where was the gun?'

Maddy could feel the sweat now beneath her arms. 'I don't know. In the waistband, possibly. At the back. In one of the pockets. I'm sorry, I just don't know.'

Mills and Ashley exchanged a look.

'So,' Ashley said, 'just to be clear, you did see Grant reaching for the second gun?'

'I saw him reaching down, yes.'

'Reaching down?'

'Yes.'

'Reaching for the Derringer?'

'I assume so, yes.'

'And you felt under threat?'

'Of course.'

'From Grant?'

'Yes.'

'Because you saw the weapon in his hand?'

'I'd just seen him shoot PC Draper. I thought he would kill me if he could.'

'So Superintendent Mallory's action was entirely justified? In your eyes?'

'Yes.'

'Even though,' Mills said, her voice sharper than before, 'you never saw the weapon in Grant's hand?'

'I saw it on the floor, beside him when he fell.'

'But not actually in his hand?'

Maddy hesitated, longer this time. 'No, ma'am, not actually in his hand.'

Linda Mills closed her eyes. Trevor Ashley smiled.

'Good,' Ashley said. 'That's all, I think, for now. Thank you, sergeant, for your time.'

Maddy felt slightly giddy as she stood.

'I should try and avoid discussing this with your colleagues,' Mills said. 'In all probability we will want to talk to you again.'

Back outside, Maddy could smell the perspiration rising off her in waves.

Maurice Repton intercepted her in the corridor downstairs, hair carefully, neatly brushed, giving off a faint smell of cologne.

'How did it go in there, anyway?' Repton asked. 'The interview. Rubber truncheons and thumbscrews?'

Maddy managed a smile. 'No, sir. Nothing like that.'

'Nothing tricky?'

'No, sir, not really.'

'No awkward questions? About the shooting?'

Maddy shook her head.

'Give you a tough time, did she?'

'Sir?'

'The Mills woman. Always come down hardest on their own kind.'

'Not too bad, sir.'

'She'll have Ashley's job while he still thinks pension is just a seven-letter word on Countdown, poor sod. Assistant Chief Constable in ten years. Equal opportunities advertisement, pictures in the press.' He took a small step back, sardonic grin in place. 'Shame she's not blessed with a touch of the tar-brush, be ACC already.'

When Maddy reached the main door, she stood fully five minutes, breathing in what air she could.

The onset of winter always affected Maddy Birch badly, the end of summer time only days away: the putting back of the clocks rocking her body in the same hormonal way as her monthly periods, sending her in search of Nurofen and curling her up beneath the quilt with a hot-water bottle held fast against her stomach.

Hurrying home on newly dark nights like tonight, the wind funnelling along the warren of streets between Holloway Road and Hornsey Rise, even the scarf tucked down inside her coat didn't succeed in keeping out the chill. If she could have afforded to keep the heating on in her flat throughout the day, she would. Anything to avoid opening the door into the same cold ground-floor rooms that, now November was nigh, smelt forever damp.

The first thing she usually did, even before taking off her coat, was set a match to the gas fire in the hearth; then she would fill the kettle and press down the switch, a mug of tea to warm her hands. If it were really cold, hot buttered toast. What she'd be like come February didn't bear thinking about.

'It can't be as bad down here as where you come from,' Vanessa had said once when Maddy had complained. 'Bloody Lincolnshire! Wind blows straight across from Siberia up there. Hear the wolves howling in the bloody night.'

On this particular night, however, there were things on Maddy's mind other than the wind: DCI Repton waiting to ask her about her session with the inquiry team, his concern all but shielded behind his bigotry, real or assumed; the superintendent's So, just to be clear, you did see Grant reaching for the second gun? – casual enough to be, almost, an afterthought. In all probability we will want to talk to you again.

Maddy pushed open the narrow gate and lifted her keys from her bag; someone had used her small square of front garden as a dumping ground for a half-empty tray of chips and mushy peas.

Stepping into her flat, in the instant between pushing back the door and switching on the light, Maddy froze, a wave of cold like electricity along the backs of her legs and arms. For that moment, her heart seemed to stop.

The doors to the living room and bathroom, both leading off the hall, stood wide open and at that time of the year she always kept them closed.

'Hello?'

Her voice sounded strange, unnaturally thin.

There was time to step back outside, relock the door, but what then?

Instead she went quickly forward into the living room, flicking on the light.

Nothing stirred, nothing moved.

Bedroom, bathroom, kitchen the same.

Maddy's breathing steadied, the adrenalin ceased to flow through her veins. What little she possessed of value was still there. A glass sat on the draining board, one she seldom if ever used. The bolt across the top of the French windows was unfastened and when she put pressure on the curved handle it sprang open, unlocked. There were slight circular marks on the outside she couldn't remember seeing there before.

The skin prickled along her arms.

After locking the windows correctly, she went through each room carefully again. Her watch said ten past eight and she was due to meet Vanessa at nine. Maddy was on the point of phoning to cancel, had the telephone in her hand, when she changed her mind.

Their favourite curry house, on Kentish Town Road, had undergone a makeover, stripping out the flock wallpaper and remarketing itself as hyper-cool, so that it now resembled an expensive canteen with discreet lighting and Egyptian cotton napkins in pale lavender. This place, in the hinterland between Tufnell Park and Archway, was more their kind of thing, bog standard, nothing fancy, fine until after pub closing time, when the atmosphere would become edgily raucous and poppadoms were liable to be sent skimming like frisbees through the gaseous air.

'Nothing was stolen, right?' Vanessa said. 'Missing?'

Maddy shook her head.

'But things had been moved around, you said? Disturbed?'

'One or two. I think so. I'm not sure.'

'And the doors out into the garden, you couldn't have left them unlocked?'

'No.'

'You're positive?'

'Yes. No. I mean, I'm always careful about things like that. But, no, I can't swear to it, no.'

Vanessa angled her head to one side. 'You're not getting weird on me, are you? Freaking out?'

'It's all very well for you,' Maddy said. 'Taking the piss.'

'I'm not,' Vanessa said. 'Here, have a piece of my chicken tikka. Cheer yourself up.'

'It's not funny.' Maddy surprised herself with the force of her voice. 'It's not some bloody joke.'