‘This is standard City speculation,’ Gillard said. ‘We’ve been in contact with Mr Lam’s firm, but he hasn’t got back to us. However, at this stage I don’t see any connection to the murder. The Roy family and the company trust between them control a majority of the shares.’

‘That’s all very well for you to say, Craig. I’m hearing a lot of talk from some senior figures at the National Crime Agency and the Met who say that we’re just out of our depth.’

‘I’ve heard that whistling buffoon Norman Champion saying exactly that.’

‘I’m not too concerned about him. But as things currently stand investigative journalists seem to be making most of the running.’

‘What do you mean?’

‘Well this, for example, from The Times yesterday morning. Simon Parr-Fielding, the partner of Prisha Roy, has a conviction for Class B possession. He is barred from being a director of a company after repeated failures to meet the listing requirements given by Companies House and is also, according to the paper, in considerable debt.’ She tossed the newspaper across to him. ‘Did you know this?’

‘No ma’am. I haven’t had a chance to interview all the members of the family and their spouses. That isn’t the direction that the evidence is leading,’

‘Oh, and in which direction is the evidence leading?’

‘We have a suspect in custody whose DNA was found at the scene of the crime and happens to work at a bicycle shop. He also lives within five minutes’ walk of where Mrs Roy’s body was found.’

‘Does he have a motive?’

‘We’re still working on that, ma’am.’ Gillard knew that this very moment Claire and a CSI team were going over Jason Waddington’s home with a fine-tooth comb. He was sure that they would turn something up.

‘The point is, Craig, that in the absence of anything for the press to get their teeth into, we are looking like we are stumped. How soon do you think you’ll be able to charge the suspect?’

‘I’d rather not do that, ma’am, until we are sure. For example, it’s not impossible that as the suspect is a regular user of the common, Mrs Roy’s coat may have innocently picked up one of his hairs when she fell. I’d prefer to see what else we can get from the murder weapon and the search of his home. We can hold him for another day or so.’

‘Okay,’ she said, picking up the phone. ‘I’m going to ring Christina McCafferty. I want her to get a statement out there that we have someone helping us with inquiries.’

He waited while Rigby rang the press officer and gave her a concise thirty-second set of instructions. Gillard would rather have waited for the DNA results from the murder weapon, but he was in no position to contest the chief constable’s judgement. She had good reasons to move fast.

Back at his desk, Gillard took a quick break to ring Sam. She was on duty in the control room, and called him back as soon as she was able. ‘Hi, it’s me, what’s up?’