London, 1938. The effervescent 'It girl' of London society since her father was named the ambassador, Kathleen 'Kick' Kennedy moves in rarefied circles, rubbing elbows with some of the twentieth century's most powerful figures. Soon, she is swept off her feet by Billy Hartington, the future Duke of Devonshire. But their love is forbidden, as Kick's devout Catholic family and Billy's staunchly Protestant one would never approve their match. And when war breaks out, Billy is ripped from Kick's arms as the Kennedys are forced to return to the States. Now, Kick will have to decide where her loyalty truly lies.