Helen Webb, politician's wife, doting mother, and professional spy, has been passing on her husband's secrets to the Black Doves, the shadowy organization for whom she works. But when her lover Jason is assassinated, Helen's life is turned upside down, and only her old friend Sam Young can keep her safe. But Sam, a suave, champagne-drinking assassin, also has problems of his own. Out of the game, since his last job went wrong, he soon realizes his past is coming back to haunt him. Together, they set off on a mission that will lead them to uncover a vast, interconnected conspiracy. One that links the murky underworld of London to a looming geopolitical crisis — and leads them to question the cost of the moral choices they've made.