Two minutes later he hung up.

‘Progress?’ asked Sam.

‘Possibly,’ Gillard replied. ‘They found an abandoned bicycle in a culvert under the A243, not too far from Ashtead Common. It’s being sent off for forensics. If the tyres match, we’re in business.’

Sam looked at her husband. ‘Did you ever work under Norman Champion? I can’t think of any other reason why you be so unpleasant about him.’

‘Ha! You’ve got a good nose, Sam. Yes, in my first three months in the Met, when I was based in East London, he gave a lot of recruits a very hard time. One of my female colleagues, a nice girl called Jill, was subjected to one of his initiation ceremonies. She was found at seven a.m. handcuffed to a roundabout in a playground, gagged and wearing only the top half of her uniform. It was January. The poor girl was half dead from exposure.’

‘Didn’t she report him?’

Gillard gave a cynical laugh. ‘You didn’t grass up your elders and betters, that was the code. This was thirty years before “Me Too”. It was considered to be part of the toughening-up process. Of course when Jill resigned, a lot of them just said: “Well, that’s the trouble with women, can’t take a joke.”’

‘Women’s lot has improved since then,’ she said. ‘Though we still get interrupted by bad-tempered men when watching TV.’

Gillard held up his hands in surrender. ‘Touché.’

Gillard had convened a mobile incident room meeting for eight a.m. on the Monday morning. He had two reasons for doing so early, despite the grumbling from attendees. One, it was well before they expected to run into any reporters, and two, it fitted well around a renewed search for a murder weapon and Mrs Roy’s missing purse. Over a hundred volunteers and twenty officers had been scouring the common from first light – 6.30 a.m.

The Khazi was freezing cold, and condensation was already beginning to run across the ceiling. With Gillard were DCs Hodges and Hoskins, financial specialist DS Shireen Corey-Williams and DI Claire Mulholland. Gabby Underwood was not invited, because he didn’t want her to know too much of the detail about the investigation. He had a feeling that this powerful family might well be as good at extracting information from the family liaison officer as vice versa.

‘All right, let’s get going,’ he said. ‘Number one priority today is to find the murder weapon or at least be sure it’s not been tossed somewhere nearby. Carl, what’s the word on the bike?’

‘Too early to say, sir.’ Hoskins put some photographs on the whiteboard and secured them with magnetic holders. ‘As you can see, it is a black and silver Trax TFS 10 mountain bike, which was well hidden under the culvert. It didn’t get there by accident.’

‘Was it rusty?’

‘Not the kind of rust that indicates it was there for long.’ He pointed to a close-up tyre picture, putting it side-by-side with one of the pictures taken by Kirsty Mockett. ‘On the face of it very similar tyres, but hopefully we will get confirmation later on. I’ve already emailed pictures of the bike to Ms Mockett, but she’s not able to say if it’s the one she saw.’