A surprise phone call, an unexpected bequest, and a mysterious portrait send wealthy entrepreneur and art collector Charles Brentworth on a perilous quest. With the help of attractive cosmopolitan art dealer Courtney Trent, he searches for the identity of the young woman in the antique portrait titled simply Lady J. Their puzzling pursuit leads them to London, the English Cotswolds, and into a dangerous web of art fraud in a shadowy art underworld. As they uncover clues to Lady J's identity, they discover an unsolved murder, art heists, and forged paintings. Their findings catapult them into a desperate race against time to prevent the theft of a valuable art collection and finally lead them to solve the riddle of their treasured, enigmatic Lady J.