The strange secret of Marie Cloarec by Alex Nicol

When Gwenn Rosmadec is hired to investigate a quiet notary's family history, he expects a routine genealogical case. Instead, he uncovers a deadly secret stretching from wartime espionage in Southeast Asia to modern-day Brittany—where stolen opium gold, hidden identities, and a ruthless conspiracy collide.

As witnesses die and assassins close in, Gwenn must unravel the truth before it destroys him—and everyone he loves.