‘Aye, well, we all need a bit of that. Have you got a few minutes? I wondered if you’d give me a behind-the-scenes tour of the place.’ By now Vera thought she had it pretty well sussed, but she didn’t want the old bats in the corner listening in.

‘Sure.’ Lisa pushed the lid onto the box and put it into her bag. She’d always been pale, but it seemed to Vera today that all the colour had drained from her face.

‘Do the staff have passes?’ They’d left the staffroom, but were still backstage. Grey walls and dust, occasional piles of unidentifiable equipment.

‘Yeah. Electronic fobs that let you in from the public areas. Very high-tech.’

‘God,’ Vera said, ‘what a nightmare! I’d lose mine in a week.’

Lisa smiled indulgently. She was the sort of woman who never lost anything.

‘And once you’re into the staff areas you have free access everywhere?’

‘That’s right.’

‘What about to the pool?’ Vera was developing the germ of an idea. They’d assumed that the murderer had got to the pool through the public changing rooms, but if there was staff access, that wasn’t necessarily the case. Again she thought she’d cocked up here, hadn’t concentrated on the basics. She should have demanded a floor plan right from the start. No, she thought. Charlie should have sorted the floor plan. It occurred to her that all the stuff about Elias Jones could be a distraction.

‘Yes, that’s this way.’ Lisa led her down a small corridor and into a space that was half storeroom and half office. In one corner there was a half-sized desk with a computer and phone. The rest of the room was taken up with floats and the bendy rubber strips used by the members of the aqua-aerobics classes. She opened another door and they looked out onto the poolside, only yards from the sauna and steam room.

Lisa pulled a packet of blue plastic overshoes from a drawer. ‘If you want to go out, you’ll have to wear these.’

Vera pulled them on and walked out onto the tiles. The bootees were exactly the same as the ones she wore at a crime scene. The pool was quiet. There was that strange echo that reminded her of aching limbs and a pounding heart. A few determined swimmers ploughed through the water and a couple of women sprawled on the deckchairs. From outside, when it was closed, the office door looked like another wall panel. It wasn’t surprising that they’d missed it. Lisa must have been following her thoughts. ‘The architect wanted clean lines,’ she said. ‘There are a couple of other storerooms, but they’re hidden too. This is the only one you can access from both sides.’

Vera joined her back in the office. She leaned her backside against the desk. ‘Do you know a guy called Michael Morgan?’