In October 1740 Murtagh Fraser takes Jamie to join the group of mercenaries that Ian Murray is serving with in France. Murtagh tells Jamie to stay with Ian and not to come back to Scotland. Jamie's wounds on his back are still raw and he blames himself for his father's death.
The mercenaries' first job is to deliver a wagon of rugs to a Jewish moneylender in Bordeaux. They are ambushed en route but manage to fight off the attackers. Some of the attackers get away with one of the rugs, one is killed and another is tortured for information. He reveals that he was part of a Jewish group of bandits who rob other Jews.
Ian tells Jamie that he will help him kill Jack Randall, but Jamie says he wants Ian to do something else for him. He wants him to go home and look after Jenny and Lallybroch. But Ian tells Jamie that Jenny has enough tenants to look after her and Jamie needs him here.
After delivering the rugs, the mercenary captain takes Jamie and Ian to meet their next client, a Jewish physician named Dr. Hasdi. Dr. Hasdi wants Jamie and Ian to safeguard and protect his granddaughter Rebekah bat-Leah Hauberger as she travels to Paris with a very old and precious Torah scroll and a large sum of money that make up her dowry. Rebekah is to marry the son of the chief rabbi of the Paris synagogue. Once the negotiations are completed, Dr. Hasdi takes Jamie into a small room and treats the wounds on his back.
Jamie and Ian go to a tavern with an attached brothel afterwards and Jamie is attracted to one of the young prostitutes. They witness one of the mercenaries, Mathieu, rape a prostitute by force in the tavern yard in front of many people, and are both left feeling disturbed and aroused by what they've seen, and guilty for not intervening.
Two days later they set out for Paris. Jamie and Ian are on horseback accompanying the coach carrying Rebekah and Monsieur Peretz who is custodian of the Torah scroll. On the second day of the journey the coach is attacked by bandits. As Jamie and Ian try to fight them off the coach overturns and Monsieur Peretz is killed. The two attackers escape and no sign of the coach driver can be found.
Jamie and Ian take Rebekah and her maidservant on horseback and decide to ride to Saint-Aubaye to seek help in righting the coach and dealing with Monsieur Peretz's body. Jamie feels unwell at Saint-Aubaye and is given some medicine by Rebekah which makes him hallucinate. While Jamie is in this non-lucid state, things get hot and steamy between Ian and Rebekah. The next morning Jamie and Ian discover that Rebekah and her maid have absconded with the Torah scroll. On questioning the ostler they learn the women left three hours past moonrise headed toward Bonnes.
Jamie and Ian split to follow the trail of the women when they get to a crossroads. Ian is met by Josef from their mercenary company who tells him that the rest of the mercenary party was attacked again by the same band of Jewish bandits they'd already encountered. The mercenaries managed to fight them off and protect Rebekah's dowry money they were guarding but four of them were badly wounded. Ian doesn't tell Josef that he and Jamie have lost Rebekah and the Torah scroll.
Jamie and Ian track Rebekah to a small manor house owned by the Vicomte Beaumont. When they knock on the door it is opened by one of the bandits who attacked the coach. He turns out to be the Vicomte, Pierre d'Anton. Jamie and Ian are ushered in at knifepoint and Ian sees that the rug which was stolen from their wagon is on the floor.
Pierre tells them that he and Rebekah have been betrothed for four years. Pierre explains to them that Rebekah's mother married a Christian and was declared dead by her father. When Rebekah was 14 she fell in love with 16 year old Pierre d'Anton and they were betrothed. But Rebecca's father died and she went to live with her grandfather, Dr. Hasdi, and embraced her Jewish heritage. Pierre vowed that he would covert to Judaism so he could still marry Rebekah, but her grandfather did not believe that Pierre would be prepared to give up his title and property which would happen if he became a Jew. He feared that Pierre would revert to being Christian and Rebekah with him once they were married.
Pierre says that he and Rebekah arranged for Pierre to abduct her on the journey to Paris and that Rebekah had told him that the rug was part of her dowry and she had had some men deliver it. Pierre locks Jamie and Ian in the wine cellar where they help themselves to the wine and figure out that Rebekah is the person providing information to the Jewish bandits about which wagons they should attack, and that the rug is her share of the profits. They decide that Pierre is ignorant of this.
That night Rebekah and Pierre are married in his garden in accordance with proper Jewish custom and the Law. They get Jamie and Ian to witness the wedding so they can tell Dr. Hasdi. When the marriage ceremony is over Jamie asks Ian to detain Pierre while he talks with Rebekah. Jamie tells Rebekah that if she doesn't give him the Torah scroll to return to her grandfather, he will tell Pierre about her involvement with the gang of bandits. Rebekah reluctantly hands over the scroll and Jamie and Ian take it back to Dr. Hasdi.
After leaving his house they go back to the tavern which they had previously visited and Jamie seeks out the brown-haired girl he was attracted to. He sees Mathieu with her and is overcome with rage. He shouts at Mathieu to let go of the girl, but Mathieu ignores him. Jamie takes out a pistol and fires at Mathieu and all hell breaks loose. Mathieu turns on Jamie, and Ian when he goes to Jamie's aid, and Jamie is overtaken with great rage and throttles Mathieu. As his rage dissipates he turns to the girl only to find that she is dead with a bullet hole in her breast, most likely from the gun that he fired.
Ian takes Jamie to the cathedral of St Andre to confess his sins, but Jamie refuses so Ian takes him into a side chapel and together they pray for the girl, for Jamie's father and for all their loved ones left behind in Scotland. They leave the cathedral and face the future together.