‘Both subjects are on the move. Patchett standing up and Bolton going for the door.’

As their transmission ended, Simmons heard a door opening and footsteps growing heavier as they approached Carter.

‘Let’s take a drive, Mr Carter. We can talk on the way.’

Silence followed by a rustling noise, then footsteps receding. Simmons turned to Gibson with a puzzled look.

‘Is it just me or is the sound getting fainter?’ Regardless of whether they were leaving at the same time or together, she still expected to hear at least one set of footsteps consistently. She raised her binoculars again to focus on the door. It opened and Carter stepped out, followed closely by Bolton.

‘Shit! Where’s his bloody coat?’ Without the mike on his jacket, they had lost their one and only audio source. Carter was like a silhouette in his light grey sweater against the backdrop of Bolton’s black overcoat.

‘The son of a bitch has double-crossed us,’ spat Gibson.

Simmons shook her head. ‘Something’s wrong, guv. He looks even more nervous than when he went in. What did we miss?’

Let’s take a drive, Mr Carter. We can talk on the way.

Carter had made his fair share of mistakes over the years but as he stooped to get into the passenger seat, he wondered if helping the police would be his biggest and perhaps last. From stories he had heard, he knew Bolton had a low tolerance for anyone who got out of line.

Bolton had suggested the drive, and then held a finger to his lips with one hand, the other reaching down and turning over the collar on Carter’s coat to reveal the mike, like a caterpillar on the underside of a leaf. He had mimed the action of removing the coat to Carter and held his hand out for the offending garment, laying it on the chair and pointing towards the door that led outside.

The cool air attacked Carter’s armpits in that brief walk to the car, and made him all the more self-conscious about the rubbery feeling of sweaty skin upon skin. He had no idea how Bolton knew about the mike, let alone where to look. He saw a man get out of the driver’s side, and climb into the back seat as they approached. He recognised the face, Daniel Stenner, one of Bolton’s right-hand men, and went to get in the back seat beside him, but felt a tap on his shoulder and saw Bolton nodding towards the front passenger seat. Bolton climbed into the driver’s seat, and the Mercedes visibly rocked side to side as he adjusted his position.

‘That’s better, don’t you think?’ he said as he started the car.

Carter looked at him blankly, his mouth hanging slightly open, unsure how to respond.

‘We can speak freely now, without our uninvited guests. Well’ – he paused and looked at Carter – ‘uninvited by me anyway.’