Ava (Jessica Chastain) is a deadly mercenary who works for a black ops organization, travelling the globe and specializing in high profile hits. Ava's career takes a bad turn when a high profile job goes dangerously wrong. Ava is told to take a hiatus from her job, until the heat blows over, but secretly the head of the organization, Simon, (Colin Farrell) has ordered a hit on her to ensure nothing traces back to the company. Ava is forced to fight for her own survival.