Armand is the head of homicide investigation at the Sûreté du Québec, visiting Paris with his wife to await the birth of their grandchild. He possesses a strong moral compass and keen observational skills honed from years of police work. Despite his professional success, he maintains a strained, distant relationship with his son.

Jean-Guy is Armand's son-in-law and former second-in-command at the Sûreté. He recently left policing for a lucrative consulting position at GHS Engineering in Paris. He harbors minor insecurities about his qualifications for the private sector and feels fiercely protective of his growing family.

Daniel is Armand and Reine-Marie's adult son who works as a banker at Banque Privée des Affaires in Paris. He acts secretive regarding his newfound wealth and his children's expensive new schooling. He lives in the city with his wife, Roslyn, and keeps an emotional distance from his parents.

Claude is the Prefect of Police in Paris and an old friend of Armand. He assumes control of the investigation when Stephen is attacked, balancing his authoritative position with his personal connection to the Gamache family. He is a seasoned investigator whose methods closely mirror Armand's own.

Stephen is a 93-year-old billionaire and Armand's godfather. He took on a fatherly role for Armand after the death of Armand's parents. A survivor of World War II with a mysterious past, he uses his wealth and connections to quietly investigate corporate matters before falling into a coma following a suspicious hit-and-run.

Reine-Marie is Armand's wife and a talented archivist. She serves as the emotional anchor for the Gamache family, mediating tensions between her husband and their son. Her specific research skills prove highly valuable when the family begins looking into the circumstances surrounding Stephen's attack.

Annie is Armand and Reine-Marie's daughter, currently living in Paris with her husband, Jean-Guy, and their young son, Honoré. She works as a lawyer and is nearing the end of her second pregnancy, providing a joyous reason for the family's gathering before the attack on Stephen.

Irena is the formidable second-in-command to Claude Dussault at the Paris Prefecture. She conducts aggressive interviews with the Gamache family and quickly unearths disturbing historical files regarding Stephen Horowitz's past, causing immediate friction with Armand.

Alexander is an engineer and investor from Ontario. He is found murdered with two professional gunshot wounds, carrying a special coded business card that indicates a highly trusted relationship with Stephen.

Séverine is an engineer at GHS Engineering who works alongside Jean-Guy. She acts distant and behaves suspiciously regarding company computers, particularly concerning the firm's international projects.

Carole Gossette is an executive at GHS Engineering and Jean-Guy's new boss. She specifically values Jean-Guy's detective background, claiming the company needs his ability to root out corruption for their humanitarian projects.

Loiselle is a security guard working for the elite organization SecurForte. He tracks and follows Jean-Guy and Armand across Paris, presenting an intimidating and highly trained physical presence.

Thierry is Claude Dussault's former second-in-command who now heads SecurForte, the elite private security firm employed by GHS Engineering.

Monique is a pediatrician and Claude Dussault's wife. She enjoys a pleasant social relationship with Reine-Marie and unwittingly provides clues regarding her husband's activities through casual conversation.

Mrs. McGillicuddy is Stephen Horowitz's long-time secretary. She holds significant knowledge regarding his schedules, meetings, and financial arrangements, proving helpful to Armand's investigation.

Madame Roquebrune is the powerful president and CEO of GHS Engineering. She employs the paramilitary security firm SecurForte and oversees the company's massive global projects.

Roslyn is Daniel Gamache's wife who has relocated to Paris with him and their two daughters.

Honoré is the young son of Annie and Jean-Guy, bringing joy and a protective instinct out of his father in their new Parisian life.