He opened the socket and screwdriver set that he had brought in from the back of the car and selected a flat-bladed screwdriver. He shoved the tip into the gap between the loose stone and a neighbour and pushed down on the handle, prising the edge of the loose stone up. Ziggy reached down, forced his fingers into the gap and heaved the stone all the way up. The stone was heavy, and the two of them muscled it out of the way.

The freshly opened gap revealed a dark void beneath the floor. Ziggy shone his light down into the space. It was deep and had been excavated so that it was wide enough to accommodate two metal Peli cases.

“Give me a hand,” Ziggy said. “They’ll be heavy.”

They rested their flashlights on the ground and both grabbed the handle of the nearest case.

“On three,” Chase said. “One, two, three, pull.”

The case came up out of the hole a lot more easily than Ziggy had expected. It was weighty, but he had anticipated it being even more cumbersome given what he was likely to find inside. The case was around a metre and a half long, seventy centimetres wide and sixty centimetres deep. They laid it down on the floor and Ziggy undid the clasps that held the lid closed. The hard shell was waterproof, and the contents were protected by a foam insert and silica gel packets.

Chase shone the flashlight down.

“That’s it?”

Ziggy stared down at the contents in puzzlement: there were two Sig Sauer P226 handguns, a lever-action rifle and a selection of ammunition in various calibres.

“Someone’s been here already,” Chase said. “Look.”

He pointed to the foam insert. There were spaces for additional hardware, but they were empty.

Chase took out the rifle. It was chambered for big-bore .45-70 rounds. “Haven’t seen one of these for a while,” he said. “Tough to get ammo for it. Might be why it was left.”

“Let’s check the other one.”

They hauled out the second case and found that the situation was worse. This one had been completely emptied.

Chase reached into the first case and took out one of the handguns. “Who else would’ve known that the cases were here?”

“No one,” Ziggy said.

“Apart from the people you used to work for.”

“Yes,” he said. “Obviously.”

“So they’ve been here.”

“There was no sign of that.”

The stash had been marked as green, meaning that it had recently been restocked by the local quartermaster. The only way that this made any sense was if Group Fifteen agents were in theatre and had visited the chapel to arm themselves.

But what would Group Fifteen agents be doing in Medellín?

“Come on,” he said, turning to the first case. “We’ll take what’s left.”