Will Robie, a freelance hitman working for the government, rescues a teenage girl whose parents' disappearance may be linked to a vast, high-level cover-up.

"Every day without fail, Travis Devine puts on a cheap suit, grabs his faux-leather briefcase, and boards the 6:20 commuter train to Manhattan, where he works as an entry-level analyst at the city's most prestigious investment firm. In the mornings, he gazes out the train window at the lavish homes of the uberwealthy, dreaming about joining their ranks. In the evenings, he listens to the fiscal news on his phone, already preparing for the next grueling...

Skilled assassin Will Robie is asked by the U.S. government to track down fellow assassin Jessica Reel, who has gone rogue, but during his pursuit of Reel, Robie realizes that her betrayal may be concealing a larger threat that could impact the whole world.