“Every day, man,” Cooper replied. “My art. I draw what’s in front of my eyes. Only a little different. Street scenes, or sometimes just one of the mansion houses. Or churches. Tourists really dig churches.”

“Could I commission a picture?”

Cooper looked moved. “Really, man?”

“There’s a mansion on Prinsengracht, the corner of Leidsestraat. Know the one I’m talking about?”

“You got good taste, man. It’s a beauty.”

The structure had been made by combining three existing dwellings, but the facade was reconstructed as if it had been built as a single estate. Eight fluted Corinthian pilasters ran under the pediment; seven bay windows faced the street. Red bands of masonry alternated with dressed stone. The world headquarters of the Liberty Foundation had history inscribed on every brick.

“Think you could do that for me now? As detailed as you can make it.” A bicyclist whizzed past, going the wrong way down the one-way street, nearly colliding with them.

“Jeepers. You know, I never knew you really grooved to my work. You always were kinda standoffish about it. Thought maybe it wasn’t your bag.”

“As much detail as you can, Barry,” Janson stressed. “Also, if you can get a rear view. Should be visible on Lange Leidsedwarsstraat.”

“I’m gonna break out my new pastels,” Cooper said. “Just for you.”

Bicyclists and street artists: two species who never got a second look in Amsterdam’s old town. Cooper could set down on the sidewalk right in front of the place and would not be noticed. He had spent decades doing so. He disappeared into the scenery because he was part of the scenery.

Back in Cooper’s houseboat, an hour later, Janson reviewed the sketches. He was not heartened. There were various points of possible egress, but none that were protected from public view. It was likely, too, that sophisticated motion detectors were in use throughout the building. And because the rear faced Lange Leid-sedwarsstraat, there would be no surreptitious way to gain entry there, either.

As a rule, there were two ways of achieving security. The more familiar method was through isolation: the castle on the mountainside, the subterranean vault. The other involved proximity and publicity: the building in the town common, where unauthorized entry was inhibited by exposure. The brilliance of the Liberty Foundation headquarters was that rather than relying entirely upon a security detail, it effectively turned hundreds of passersby—the denizens and pedestrians of the city itself—into sentinels. It was protected, ultimately, by being in plain view.

Janson was annoyed at himself: he was thinking inside the proverbial box, was coming up with solutions that had served him in the past but were inappropriate to the situation he now confronted. He needed to think differently.