“It’s a remarkable story,” said Gabriel. “And I believe every word of it. Kurt Voss was an easy mark. He was a notorious war criminal, a wanted man. For more than twenty years, the fortune was sitting in Landesmann’s bank growing by the day. At some point, Landesmann decided Voss was never coming back, and he convinced himself the money was his for the taking. So he closed out the accounts and destroyed the records.”

“And a fortune of looted Holocaust assets vanished into thin air,” Chiara said bitterly.

“Just like the people it once belonged to.”

“And the painting?”

“If Landesmann had had any sense, he would have burned it. But he didn’t. He was a greedy bastard. And even in 1964, before art prices skyrocketed, the painting was worth a great deal. I suspect he entrusted it to the Hoffmann Gallery of Lucerne and arranged for a quiet sale.”

“Did he know about the list?”

“In order to find it, he would have had to pull apart the two canvases and look inside. But he had no reason to do that.”

“So it was still inside the painting at the time of the 1964 sale?”

“Without question.”

“There’s one thing I don’t understand,” Chiara said after a silence. “Why kill Carlos Weber? After all, Landesmann had quietly turned away Voss’s wife when she came looking for the money. Why didn’t he do the same when Weber appeared in Zurich?”

“Perhaps it was because Weber’s visit was quasi-official. Remember, he was representing not just Voss but the government of Argentina. That made him dangerous.” Gabriel paused. “But I suspect there was something else that made Weber even more dangerous. He knew about the Rembrandt and the list of account numbers hidden inside it. And he made that clear to Landesmann during their meeting.”

“And Landesmann realized that he had a serious problem,” Chiara said. “Because whoever was in possession of the Rembrandt also had proof that Kurt Voss’s fortune had been hidden in Landesmann’s bank.”

Gabriel nodded. “Obviously, Landesmann said something encouraging to Weber to keep him in Zurich long enough to arrange his death. Then, after Weber’s unfortunate fall into Lake Zurich, he no doubt undertook a frantic search for the painting.”

“Why didn’t he just go back to the Hoffmann Gallery and ask for the name of the person who bought it in 1964?”

“Because in Switzerland, a private sale means a private sale, even for the likes of Walter Landesmann. Besides, given Landesmann’s precarious situation, he would have been very reluctant to call attention to himself like that.”

“And Martin?”

“I suspect that, at some point, the father confessed his sins to his son, and Martin took up the search. That Rembrandt has been floating around out there like a ticking time bomb for more than forty years. If it were ever to come to light…”

“Then Martin’s world would be shattered in an instant.”