Synopsis
John Knox works a day-to-day job as a contract killer employed by Xavier Crane, a crime boss. He is estranged from his wife and son and dates a Cracovian immigrant named Annie, who shares his love for books. Knox is later diagnosed with a fast-moving form of dementia called Creutzfeldt–Jakob disease. He quickly makes arrangements to cash out and retire from the business. Before that, he undertakes one last job with his partner, Thomas Muncie.
During the job, after successfully killing his target but also accidentally killing the woman who was with him in the shower, Knox accidentally kills Muncie in his dementia-fueled confusion. He quickly stages the scene and leaves. That night, he is suddenly visited by his estranged son Miles, who tearfully admits to killing a man for raping his daughter, Knox's granddaughter. Knox instructs his son to remain quiet to the authorities as he later arrives at the crime scene and meticulously removes evidence that may incriminate Miles, while mysteriously storing them away for later use. Meanwhile, dogged detective Emily Ikari is on both murder cases, determined to pinpoint the perpetrator.
Knox later visits his friend and boss Xavier Crane, a crime lord. Together, they cook up a plan to set Knox's family up for life while leaving the business behind, all while Knox battles his fading mental state. Meanwhile, Detective Ikari links both crimes to a single perpetrator. She interrogates Knox to no effect. He plants the evidence he had previously stored away around his son Miles' home, seemingly betraying him. Miles is arrested for the murder of his daughter's rapist, and is confronted by Knox in prison, where Knox accuses Miles of ratting him out in a tax evasion case several years prior. After getting lost in the woods after digging up his stash of diamonds at a cabin his family used to own, Knox is picked up by Crane and driven home. Upon reaching home, he is confronted by a group of burglars and Annie, who had become aware of Knox's dementia and the fact that he had been cashing out and ratted him out as a result. Killing them all, Knox confronts Annie at gunpoint and informs her that she would have gotten a share anyways. Despondent, Knox calls Xavier, who wishes him fortune before informing the police as part of their plan, whereupon he is arrested by Detective Ikari. The police later discover signs that the evidence found at Miles Knox's house may have been tampered with, and planted there by Knox, leading to the conclusion that Knox may have framed his own son for the murder. When asked by Ikari on a possible motive, Miles, recalling his father's accusation of him in prison, responds accordingly, shifting the blame fully over to Knox. He is then released.