1947. As the royal wedding of Princess Elizabeth and Prince Philip whips Britain into a fever, three friends-turned-enemies are reunited by a mysterious encrypted letter - the key to which lies buried in the long-ago betrayal that destroyed their friendship. A mysterious traitor has emerged from the shadows of their Bletchley Park past, and now Osla, Mab, and Beth must resurrect their old alliance and crack one last code together. From the bestelling author of "The Huntress"