It was a horrible thought that there might be a rat on the team, but it had to be a distinct possibility given that all our private phone numbers had been leaked.

The Southside Arms was sandwiched between two apartment buildings close to the riverfront in Rotherhithe. It boasted two bars and a large restaurant.

There were three floors above it and Roy Slack’s office was on the top floor. Access was either through the pub or through a door to the side that had a video intercom and a security camera.

As we came to a stop in front of the building I was the first onto the pavement followed by six uniforms and Kate.

‘I’ll take the side door,’ I told her. ‘You go through the pub.’

I was about to give instructions to the uniforms when the side door opened and a man stepped out onto the pavement. He raised a hand towards me, palm facing out.

‘There’s no need to go storming inside like a fucking army,’ he said. ‘There are people in there enjoying their lunch.’

He was at once familiar to me from the many photos I’d seen. His name was Danny Carver, but in the underworld he was known as The Rottweiler.

‘I’m Detective Inspector Laura Jefferson from the organised crime task force and I’m here to speak to Roy Slack,’ I said. ‘I also have a warrant to search his office.’

He smiled then, flashing a couple of gold teeth that made him look like a pirate.

‘Well, you’re in luck, my love,’ he said. ‘He’s upstairs, and he’ll be happy to answer your questions, whatever they’re about.’

It was not the reaction I’d expected, but I didn’t let that faze me.

As I stepped towards him I was struck by how big and ugly he was. He had a barrel-chest beneath a black T-shirt and thick arms adorned with tattoos. His dark hair was short and spiky and his broken nose was pressed flat against the rest of his face.

‘Were you expecting us?’ I asked when I stood facing him.

‘How could we have possibly known you were coming?’ he said, grinning. ‘You didn’t have the good manners to tell us.’

I turned to look at Kate and she rolled her eyes. It was all too obvious that they’d been forewarned, and that concerned me.

I instructed two uniforms to wait outside and question anyone who left the building, then told Carver to take us upstairs to his boss.

It felt like an anti-climax. I’d been bracing myself for a loud, hostile reception, but instead we were being treated like welcome guests. That in itself was a bad omen. Either Slack had nothing to hide or he’d hidden it where he knew we would never find it.

‘So what goes on up here?’ I said as we mounted the stairs.