Geoff Birley had stopped speaking. He licked his lips anxiously, as if he’d forgotten what he was saying. He seemed to know they were expecting something of him, but wasn’t sure what it was. He looked up at his sister, who was standing over him like an attentive nurse.

‘Well, I’m just saying, Trish,’ he said. ‘About the car park.’

Trish Neville sighed and folded her arms across her chest. She looked at the two detectives. Over to you, she seemed to say.

‘Despite that, your wife used the multi-storey car park regularly, didn’t she, sir?’ said Fry.

‘Yes, she did,’ said Birley. ‘But she always tried to get a space on the lower levels, so she wouldn’t have to go up to the top to fetch her car if she worked late at the office. Only, you have to get there early, you see. You have to be there at seven o’clock, or you’ve had it for the rest of the day.’

‘And she was late yesterday morning?’

‘She got held up by a phone call as she was leaving the house. It was only her mother, mithering about nothing as usual. But Sandra always has to spend a few minutes listening to the old bat and calming her down. Sandra is like that – if she cut her mother off short, she’d have felt guilty about it all day. So she made herself late because of it. By the time she got to Clappergate, the bottom levels of the car park would already have been full. A few minutes make all the difference, you see. And when that happens, you have to go up and up, until you’re on the bloody roof.’

‘Her car wasn’t quite on the roof level, in fact,’ said Fry. ‘It was on the one below, Level 8.’

‘She was lucky, then. She must have nipped into a space.’

Fry and Hitchens exchanged a glance. The fact that Mr Birley should still be describing his wife’s actions as ‘lucky’ told them that reality hadn’t sunk in for him yet. The one thing Sandra Birley hadn’t been last night was lucky.

‘Mr Birley,’ said Hitchens. ‘When your wife went back for her car, we think she used the stairs to get to Level 8, instead of the lift. Yet the lift was working. Would that have been her usual habit, do you think?’

The question seemed only to confuse Geoff Birley. ‘How do you mean?’

‘Would your wife normally have used the stairs to go up eight floors, rather than take the lift?’

Birley hesitated. ‘It depends. What did it smell like?’

Now it was Hitchens’ turn to look puzzled. ‘I’m sorry, sir?’

‘The lift. What did it smell like? Did anyone open it and have a smell inside?’

Fry had been present when the lift was examined. Even now, she had to swallow a little surge of bile that rose to her throat as she remembered the stink.

‘Yes, it smelled pretty bad.’

‘Like somebody had thrown up in there, then pissed on it?’