Cornelia Small has settled comfortably into a new life, teaching English in the slums of Bangkok. But one day an artifact in a shop window changes everything, and soon Cornelia is drawn into a mystery that's entwined with her own past. She has stumbled upon the sought-after painting Satanic Christmas, which is said to hold a secret message about the end of the world. It was painted by her old neighbor, Miss Grace, who encoded within its brushstrokes the identity of the two witnesses described in the book of Revelation. Feeling as though she's on a trip back in time, Cornelia returns to her childhood home in the Ozark Mountains to see Miss Grace. She is greeted by shocking news that makes her mission more difficult-and more personal. After returning to Thailand, Cornelia travels to a remote monastery where the witnesses may live. Before she can reach her destination, chaos catches up with Cornelia and her passionate boss, Chanya. The painting disappears, and Cornelia is framed for murder. Their only hope is to solve the final clues, but not everyone wants the truth to come out.