Forty-five minutes later, when Hembury turned the corner of Vine on to Sunset, Wicks spotted him in the rear-view mirror and, ten seconds later, had armed himself with a loaded syringe and was out of the Jeep. He nonchalantly crossed the road and fell into place about ten steps behind his prey. His clenched fist managed to keep the syringe totally hidden from sight. Hembury was about twenty yards from the front entrance of the apartment block and could sense Wicks rapidly closing the distance behind him.

As he prepared to strike, Wicks subtly adjusted his grip on the syringe and the needle was suddenly visible in his left hand.

At the last moment, Hembury and Vargas performed a perfectly timed pincer move on the unsuspecting hitman. Vargas had been holding position behind a clump of bushes by the side of the block for the last ten minutes and had kept his eyes firmly trained on Wicks from the moment he left the Jeep. The hitman was less than five feet away when Hembury spun around with his right arm raised, his Smith & Wesson aimed directly at his attacker’s head. Wicks had been just a hair’s breadth away from striking and was momentarily stunned by Hembury’s last-second manoeuvre. Instinctively, he turned on the spot and started to race towards the Jeep. He only managed four steps before he was taken down by a perfectly timed rugby tackle, courtesy of Vargas, who seemed to appear from nowhere. He slammed into Wicks and the sheer impact of the collision sent the syringe flying from his grasp.

Having wrestled him to the ground, it only took a few seconds to position him face down on his front, with his arms firmly pinned behind his back. Hembury knelt down and held the gun inches from Wicks’s head. He used his other hand to retrieve a pair of heavy-duty handcuffs and passed them to Vargas. At that exact moment, the sound of an engine fired up and both detectives glanced across the street to see the Cherokee pull away and disappear around the corner.

Vargas pulled Wicks up off the pavement and frogmarched him towards the entrance of the apartment block with Hembury walking alongside, his gun still drawn. Once they were inside, Hembury sat him down on one of the kitchen chairs and reset the handcuffs so his wrists were tied behind the back of it. Vargas was standing by the sink, emptying the contents of the syringe into a drinking glass. He had no doubt the liquid it contained was lethal. He walked across the kitchen and held the glass in front of Wicks’s face.

“Fancy a drink? What is this stuff?”