We had no choice but to hand it over to Vice and move on. The old cop cliché of the first forty-eight hours being crucial is sort of true, and we were well over that. The case started floundering. We felt like fish in a drying riverbed. First there were leads that went nowhere, then there were just no leads. Desperation started to grip us. We were inching closer to the unthinkable, an unsolvable murder. And the pressure weighing down on us from above, pressure that was undoubtedly initiated by Judge Muller himself, was increasing exponentially. It felt like gravity itself was suddenly no longer obeying its own law.

‘Finished with that?’

I look up to see mop man pointing to the can in front of me. I pick it up and toss it into the black bag he’s holding open. He ties it up and shuffles away.

We’d had to go back to the drawing board. Alternative theories were tossed around, some plausible, some just about possible, some utterly preposterous. We pushed ourselves to think outside whatever box we were obviously trapped in, but still we were going nowhere. Joel once told me it’s hard to see what’s on the label when you’re in the jar itself. Then Station Chief Smit, under pressure himself, took the unusual move of joining our investigative team. We didn’t like it, but then again it was clear we needed help.

No one who worked with the man would ever have characterized his presence as a good omen, and yet in this instance, soon after he joined us we got lucky, a phone call that changed it all.

A man called Burt Dankert who’d been working a few streets away around the time of Muller’s death, part of a crew digging up the road to lay fibre-optic cable, was on a break when he recognized a man walking past in a hurry. The name of the man, Dankert claimed, was Sander Klaasen. They’d worked together on a building site up in Alkmaar the previous summer, Dankert explained. Klaasen had quickly gained a reputation for being an outsider, not fitting in with the crowd, moody and just about cooperative enough to keep his job, but nothing more. So he wasn’t that surprised when he called out to him only to have Klaasen blank him completely. Dankert shrugged his shoulders and went back to work, thinking nothing more of it until a couple of days later he caught sight of a newspaper with stills captured from the footage we’d released. What he saw stopped him dead; the man we were looking for was wearing the exact same hoody and cap Klaasen had been when he’d walked right by him.