1968 Hunter's Point, California. After the teens have a brief encounter with a police officer, The Zodiac Killer murders David Arthur Faraday and Betty Lou Jensen on Lake Herman Road. Present Day, Virginia. Taking a risk to change his poor financial situation, landscaper Mick Bradley purchases an abandoned storage locker with his pawnbroker friend Harvey. Among the items retrieved from the unit are home movie reels of the Zodiac murders filmed by Zodiac himself. Despite her initial hesitancy, Mick's wife Zoe agrees to help Mick and Harvey investigate the reels in hopes of obtaining a $100,000 reward for information leading to Zodiac's capture. Meanwhile, Zodiac captures Tina, the woman who manages the storage unit facility, and slits her throat with a knife. Mick and Zoe break into the storage facility office to find out who rented the Zodiac locker. They discover it was rented under the name Betty Ferguson. After obtaining Betty Ferguson's address, the couple has a brief showdown with a man in the shadows outside. Mick's trailer park neighbor Ray warns him about pursuing Zodiac. Mick, Zoe, and Harvey break into the house belonging to Betty Ferguson and her husband Balthazar. While trying to steal another film reel, the trio is confronted at gunpoint by Benjamin Ferguson. Benjamin reveals he is Betty and Balthazar's son. His parents, both in their nineties, actually live in Florida. Benjamin gives Harvey a business card identifying him as an editor at the Tri-County News Ledger. As Benjamin dismisses the trespassers, a nearby neighbor briefly asks if everything is okay. Harvey spots a cipher key while reviewing one of the film reels. While Harvey uses the key to work on decoding the unsolved Zodiac cipher, Zoe goes to the town hall to research records on Benjamin Ferguson. Zoe discovers Benjamin's background is consistent with Zodiac's and Benjamin can be placed in San Francisco in the 1960s, where he worked at a newspaper following the Vietnam War. However, Benjamin had already moved to Virginia, as he had been writing investigative articles while pursuing a theory that Zodiac was moving east, at the time Zodiac murdered cabby Paul Stine. Despite contradictory evidence, Mick continues under the pretense that Benjamin is Zodiac. Zoe becomes concerned with her husband's erratic behavior when strange events begin making Mick paranoid. Mick and Zoe check in with Harvey, who dismisses them so that he can continue solving the cipher, which will reportedly reveal the Zodiac's name. When the couple returns later, they find Harvey missing, and initially assume he abandoned them to claim the reward money alone. Mick investigates the space above the pawnshop when he notices something dripping from the ceiling. Zoe sees Harvey's van peeling away outside and, assuming Harvey is trying to get away from them in a hurry, immediately gives chase in Mick's truck. At the same time, Mick discovers Harvey's murdered body upstairs and realizes his wife is in danger. Mick frantically races to the Ferguson house, where he finds Benjamin dead in his car with his throat cut. Mick also finds a Zodiac cipher written on the car door. Zoe tracks Harvey's van to a remote farm. When her guard goes down, Zodiac captures her. Zodiac then calls Mick from Zoe's phone with a taunt and a threat to not contact police. With Zoe held captive, Zodiac explains that he hadn't killed anyone for 40 years. He had followed Ben from San Francisco because he knew Ben was close to uncovering his identity, but grew to enjoy life in Virginia as Ben's unassuming neighbor. Forgetting to make payments on his storage locker compelled Zodiac to resurrect his crime spree to protect his identity. Mick arrives at the farm for a face-off with Zodiac. Over the course of their confrontation and gun-play, Mick manages to free Zoe. The face-off continues all over the farm until Zoe brings Zodiac to the ground and Mick then shoots him in the throat. Four weeks later, the FBI and local authorities continue investigating the recent murders. Mick exits the trailer to fix a light and seemingly vanishes. Worried, Zoe goes outside to check on him. An ominous foot sets down in the foreground.