For former spies, even entertaining is fraught with danger. In April 1818, the London Season is in full swing, but the aftermath of the Napoleonic Wars lingers. Malcolm and Suzanne Rannoch are hosting their first ball since the revelations about Suzannes past that nearly destroyed their marriage. The Rannochs are just learning to trust each other again. But in the midst of the waltzing and champagne, old friends from the spy game slip in through the window of the Rannochs' Berkeley Square house, bringing a message from Suzannes past. While their guests dance and flirt, Malcolm and Suzanne confront old dangers and new enemies that could upend their fragile peace.