November 1932. Sister Mary Catherine of the Order of Perpetual Sorrow asks private eye Lazarus Flynn for help in expanding the Order's orphanage. When a job comes up that involves a simple trip to Manhattan to pick up a mysterious artifact, Flynn accepts, hoping to secure the funds to finance the expansion.

In Manhattan, Flynn quickly becomes the chief suspect in a murder involving an ancient book of magic spells and sets out to clear his name.

To his suprise, he is ensnared in a deadly search for stolent red diamonds involving a dying millionaire, a Russian mobster, a Romanian countess, an Interpol investigator and an elusive criminal mastermind known only as The Jackdaw, all searching for six legendary red diamonds.