Left to his own devices, he’d re-entered the premises and had a good look round.

That’s when he’d found the out-of-date ticket to the Go Wild fight club, which he’d pocketed, promising himself to check out the location at least.

The place looked all shut up when he got there apart from the red light above the door. McNab stood for a moment listening, convinced he could hear voices raised somewhere in the building. He banged on the door three times and waited.

When nothing happened, he tried again. Having got there, it would be unfortunate if he never crossed the threshold. He fished in his pocket and brought out the invitation he’d found in a desk drawer of the boarded-up Go Wild office. Out of date, of course, but they might accept it, especially if the place had been closed down for a while.

A slot in the door opened and a pair of mean eyes stared out at him. McNab displayed his invite.

‘Out of date,’ came a voice. ‘You’ll have to pay again to enter.’

‘Sure thing,’ McNab said. ‘How much?’

The door opened and he was faced with a guy as broad as he was tall. ‘Fifty to watch. Bets extra.’

He was waved towards a booth where a young woman was only too willing to swipe his card.

‘You placing a bet?’ she said with an interested look.

McNab wasn’t sure if the smile was for him or the contents of his wallet.

‘I’m just here to watch,’ he said.

‘Shame, I was going to recommend you bet on the blond.’

McNab tucked his card back in place. ‘Maybe the next bout.’

‘This is the last tonight. You should have come earlier.’ She pointed him in the direction of another door. ‘It starts shortly. Bar’s inside. No photos,’ she warned him, indicating the bouncers. ‘Or you’ll lose your phone.’

If entry was fifty pounds, McNab wondered what a drink would cost. As he approached the inner door, it was opened by the first bouncer’s twin brother, who examined his receipt, then stood out of his way.

The smell that hit him like a wall was a mixture of male sweat and fresh blood with a splash of piss, coming from somewhere near the back. McNab made for the bar, skirting round the crowd of about sixty men of varying ages. He had a quick scan of the faces, but none were recognizable from this distance. As well as the bouncers at the entry point, he spotted two other guys who looked like handlers. They had certainly marked his late entry.