Vivienne La Fleur is one of London's most sought after opera dancers and one of England's best weapons: the spy known as the Flower. When a French agent pressures her to change allegiance by abducting her sister, Vivienne is forced to seek the help of the only man in London who doesn't want her. Maximilian Westwood, retired code breaker, doesn't like surprises or mysteries and the Flower is both. When she sneaks into his study in the middle of the night with a coded message, he's ready to push her out whatever window she arrived through. Except Maximilian is unable to turn away a woman in trouble. Determined to rescue Vivienne's sister, they engage in a game of cat and mouse with French spies that requires all of Vivienne's training and Maximilian's abilities. Bound together by secrecy, they discover there is more between them than politics and hidden codes, but love has no place among the secrets of espionage...