Timothy Carrier is an unremarkable stonemason who is mistaken for a hitman by a stranger who delivers him an envelope containing $10,000 and a photo of the intended victim, a writer called Linda Paquette while drinking at his regular tavern. Soon after, the real murderer comes, and Tim manages to deceive him by claiming to be the client, stating he's changed his mind and is canceling the hit while paying the killer $10,000 as a "no-kill fee."
Tim follows the murderer outside secretly and is taken aback when the hitman installs a roof-mounted police light on top of his car before driving away, hinting the hitman is an officer. Tim pursues Linda and runs. He calls his old friend Pete, a murder investigator, and begs him to track down the killer's license plate. Tim and Linda barely keep one step ahead of the killer, and they begin to assume that he has practically limitless access to cell phones, bank transactions, and GPS monitoring, hinting that he works for someone extremely powerful. Linda begins to assume Tim is more than just a mason as Tim repeatedly foils the killer.
The incredibly confident/psychotic killer isn't discouraged, but he looks to get more unhinged as the hunt progresses. Tim and Linda develop affections for one another over time. Linda tells Tim about her disturbing background; her parents, former preschool instructors, were wrongfully convicted of horrifying sexual crimes against their kids, including their daughter. Linda was separated from her parents since both of them were sentenced to prison and finally died.
After tiring of following Tim, the murderer goes to Tim's house and kidnaps Tim's mother, then contacts Tim to arrange a deal for Linda. During the conversation, Tim's mother informs him that they are still in her place (the hitman implied they were far away). Tim and Pete race home to save Tim's mother and to assassinate the hitman. FBI officers storm the residence and begin cleaning everything up. However, Tim and Pete spot them approaching, and, suspiciously, Tim phones his friend across the street and asks him to discreetly record the agents.
The main agent discloses that the hitman was actually working for an American politician who is part of a clandestine plan to take over the American government from the inside. An adviser to that politician had lunch with a member of a terrorist group two and a half years prior. The proprietor of the establishment photographed several of his usual clients, capturing the aide and terrorist in the background. Later, the terrorist was identified as a member of a terrorist organization, while the politician rose to prominence and was being discussed as the future president, and the photographs were published on the restaurant's website. Fearing that their affiliation with a recognized terrorist organization would be revealed, the conspiracy sent the hitman to kill the customers in the photos, one of them was Linda Paquette. Before departing, the lead agent apologizes graciously for creating so much bother but warns Tim that if any of them ever say anything about what occurred, Tim and everyone he loves will be murdered, and the death will be misconstrued as a murder/suicide due to Tim's PTSD. Later, Pete tells Linda about Tim receiving the Medal of Honor for saving several people during his time as a Marine.
Tim shows the tape to the current president of the United States and tells him about the secretive organization of government insiders. The narrative concludes with Tim and Linda married and the plot crumbling; there are several arrests and suicides.
