Kellan and Vienna Knox, a couple in a stagnating marriage, live a deceptively mundane existence. However, each has been hiding a secret from the other: they are trained assassins working for adversarial agencies. When they are both assigned to kill the same target, Kyle Sanders, the truth comes to the surface. Finally free from their cover stories, they discover that they have been assigned to kill each other, sparking a series of explosive attacks and sexual desires. **Credited to the directors, producers, writers of the movie , Mr. & Mrs. Smith, which this novel is based on.**