The movie opens with Lee separating from his mother in Antigua. His mother has to leave him at home due to her job. In subsequent days, as a lone teenager, Malvo comes in contact with John. Muhammad is living with his three children – one daughter and two sons. After spending some time together, Muhammad and Malvo move to Tacoma, Washington. Muhammad, along with Malvo, starts living there with his girlfriend, Angela (Cassandra Freeman). Muhammad starts introducing Malvo as his son.
Muhammad subsequently meets his old time friend, Ray (Tim Blake Nelson), while going for a jog with Malvo. Ray introduces Malvo to guns. Malvo turns out to be a natural marksman. One day, Muhammad tries to contact his children in Maryland but is unsuccessful due to a restraining order. Frustrated by this, Muhammad comes home and has a spat with Angela over some petty issue. Angela subsequently throws both the men out of her house. Muhammad and Malvo move in with Ray and his family. Ray lives with his wife (Joey Lauren Adams) and toddler son. Malvo discovers a cache of arms in Ray’s basement. Gradually, Muhammad brainwashes an impressionable Malvo into committing murders. Malvo commits his first murder by shooting a neighbor (Maya Woods) point-blank in the head. Muhammad encourages Malvo to commit more murders in order to pay back the favor of bringing Malvo to the U.S. Malvo commits his next murder by shooting a pub owner (Bruce Kirkpatrick) in the back and then robbing him. With the robbery money, Muhammad and Malvo buy a Caprice Classic. Muhammad subsequently teaches Malvo to drive. Muhammad also modifies the car trunk so as to make a rectangular slit in the rear which is later used to shoot a sniper rifle from.
John Muhammad and Lee Malvo subsequently conduct a siege of terror on the Washington, D.C. metropolitan area. They conduct a series of random shootings in public places. They use a rifle fired from the trunk of a blue Chevrolet Caprice. One night, while parked in a no-parking spot, the local police department catches up with them and subsequently the FBI is shown as taking over the investigation. After five months, Malvo is held in Graymore State Prison, Virginia. He is visited by a female lawyer (Linda Powell) who tries to question him about the motives of all the random killings. Malvo remains stubborn and asks, “Where is my father?” The movie closes with Aspen Hill City Police escorting Malvo back to the prison cell.