Ex-Navy Seal Nolan Kilkenny is still grieving a personal tragedy when he is unexpectedly called to the Vatican, where the dying Pope Leo XIV has a secret mission for him: rescue Chinese religious prisoner Yin Daoming, who—unbeknownst to the rest of the world—has been a secret cardinal for 20 years. Entrusted with the dangerous truth about an unreported atrocity committed against the underground Church in China and its link to the mysterious Yin Daoming, Kilkenny grimly sets out on a complicated journey that will take him from the Vatican to the U.S., China, and Mongolia, and will ultimately involve the C.I.A., the Mafia, Amercian Special Forces, a conclave of cardinals, and the U.S. President.