The Rembrandt Affair

 is the tenth book in the Gabriel Allon series. A previously unknown painting by Rembrandt is stolen and the man restoring it is murdered. The convoluted trail leads to a Swiss industrialist doing business with a nation hostile to Israel.

England
Gabriel Allon has retired from the Office. He and Chiara have come to live in Port Navas while they recover from their ordeal in Russia; Timothy Peel is the first to see Gabriel return and occasionally visits him.

While Gabriel and Chiara rest, Julian Isherwood arrives with a story about an uninsured, stolen painting by Rembrandt, a prediction of financial ruin and a plea for help. Julian tells Gabriel that he had acquired the painting and was having it restored when |the restorer was murdered and the painting, all forty-five million dollars worth, stolen. Gabriel tells the story of the painting, Portrait of a Young Woman, to Chiara, who tells him he should find it. Gabriel and Chiara are allowed to visit the scene of the crime and Gabriel concludes that one of the shots fired went through the painting. He tells Chiara they have to start where the painting did, Amsterdam.

Amsterdam
Julian Isherwood arranges for an art dealer in Amsterdam to provide a copy of the provenence of Portrait of a Young Woman to Gabriel. From the documentation, Gabriel concludes that Jacob Herzfeld, a Dutch Jew, probably had the painting stolen from him during World War II. Inquiries lead Gabriel and Chiara to Lena Herzfeld, who tells how the painting fell into the hands of an SS officer named Karl Voss. Eli Lavon verifies that the signature on the bill of sale Lena had kept really is that of Voss.

Argentina
In Argentina, Gabriel Allon and Chiara Zolli meet with Peter Voss whose father Karl had stolen the painting belonging to Lena Herzfeld's father. Peter Voss explains that his father had left his money and the painting in the custody of a bank owned by Walter Landesmann, Martin Landesmann's father. When Peter's mother attempted to claim the property, she was told that there was no account in her husband's name.

Afterward, Alfonso Ramirez gives Gabriel information about the attempts of the Argentine government to recover some or all of Karl Voss's illegally obtained fortune by a diplomat named Carlos Weber who was murdered during his search. Shortly thereafter, he is killed by a bomb in his building that was almost certainly intended to kill Gabriel and Chiara Zolli.

Gabriel calls the Office station in Buenos Aires to request an emergency extraction.

Plans
Uzi Navot disapproves of Gabriel's interest in Martin Landesmann, but Ari Shamron goes behind Uzi's back and tells the Prime Minister. The Prime Minister likes Gabriel's idea. Gabriel assembles his team plus some technical experts.

Assignation
Zoe Reed meets Martin Landesmann in Paris for a night of sex. During the night, while Landesmann is sleeping, Zoe installs software on Landesmann's cell phone and notebook computer that allows the Office to have complete access to both devices.