He went back into the house and found Forsyth sitting on the edge of the kitchen table. He was tuning the radio—a delicate touch, face blank and averted. Vincent wasn’t sure if this was a task in itself or a method for procrastination. The static faded and intensified and faded again. Leo came inside and called out something in Spanish, a sing-song tone. Forsyth removed his hand from the dial and let his fingers hover. Then he looked up at Vincent with an expression of quiet satisfaction.

He said, ‘You need the proof now, I guess?’ He stood up. ‘Come and see.’

The air inside the barn was dusty, and Vincent had to swallow the urge to cough. Light filtered in through the gap-tooth siding, white blades in different widths and inclinations all along the sides of the building. There were offcuts of lumber and rusted tools heaped along the side walls, with only just enough room in the centre to accommodate the truck. It was an Isuzu single cab, white, with a boxed-in load space and a refrigeration unit jutting out above the cab.

The truck’s rear door was ajar, and Forsyth swung it open. The deck was stacked with cardboard boxes. A box near the door was open, and Vincent saw it was packed with cans, just the lids visible, dull metal circles configured four-by-four.

Forsyth removed a can and passed it to Vincent. Pumpkin soup, bearing a Lamar’s logo, just like he’d seen in the panic room at the house.

Forsyth said, ‘Clever system. It’s about sixty per cent fluid, with a shrink-wrapped package of brown heroin in the middle. No point X-raying, because you won’t see anything through the metal. The weight’s correct. The only obvious giveaway is when you shake it. It doesn’t feel right. The dynamic properties are wrong.’

He was looking at Vincent, wanting him to try it. Vincent shook the can.

‘You see?’ Forsyth had brightened up, enthused by his little niche. The chance to expound on illicit cunning. ‘They’re doing research on how to cheat the sensation. Very sophisticated. A shaken fluid has two components, basically: impulsive and convective. The convective is the slosh component, and the impulsive is the portion of the fluid that moves with the can. But you change the contents, you change those properties, obviously. The wrapped package isn’t a fluid. But it all comes down to stiffness—internal stiffness. They have a laboratory in Coahuila, and they’ve got people with PhDs testing springs—I mean, putting a spring on each side of the package inside the can—top, bottom, each side. You know …’ He took the can off Vincent, held it up and shook it. ‘So it feels right. So the internal mass responds right. Incredible, huh?’

Yeah, it was incredible, but not in the way Forsyth thought. Vincent stood looking at the stacked boxes. He said, ‘Did Lamar know about this?’