Jeffrey Beaumont is a college student who returns to his home of Lumberton, North Carolina after his father suffers a massive stroke. He finds a severed ear, which leads him into the dark world hidden underneath his seemingly ideal American hometown.
After his father suffered from a near-fatal stroke, Jeffrey returned from college back to his hometown of Lumberton, North Carolina. He made his way to the hospital, where his father was bedridden, unable to speak, only able to cry.
He went to a vacant lot to throw pebbles until he stumbled upon a severed ear. Placing it in a bag, Jeffrey took it to Detective John Williams of the Lumberton Police. Williams took it to the coroner, who stated that its owner could still be alive and that it was cut off with scissors.
Later, Jeffrey went out for a walk, stopping at the Williams home to speak with the Detective. However, Detective Williams informed him that he could not release any details about the investigation. Shortly after leaving the Williams home, he encountered their daughter, Sandy, who told him that she frequently overheard details about a woman singer somehow related to the case.
Sandy showed him to the apartment building that the singer lived in on Lincoln Street. They turned back, walking and talking as Jeffrey took in his old hometown.
He picked up Sandy from school the next day and took her to Arlene's Diner. There, he told her his plan to get into the singer's apartment, posing as a pest control worker. After learning the singer's name to be Dorothy Vallens, Jeffrey made his way to her apartment with a bug-spray rig and stole a key when Vallens went to answer the door, where there was a man in a yellow suit.
Jeffrey convinced Sandy to cancel her date with her boyfriend Mike in order for them to go to the Slow Club, where Vallens sang. There, Jeffrey drank Heineken and watched Vallens perform "Blue Velvet" and "Blue Star." They went back to Vallens' apartment and agreed on having Sandy honk the horn if Dorothy was arriving. However, due to his consumption of Heineken, Jeffrey urinated at the apartment and did not hear the horn when he flushed the toilet.
After hearing someone unlock the apartment door, he quickly hid inside of a closet. He watched as her phone rang and she begged a man named Frank to let her speak to another man named Don, whom she asked about the well-being of Donny. After the phone call, he accidentally knocked down a hanger, and Dorothy discovered him. She threatened him with a knife, believing him to be a voyeur. She had him undress at knifepoint and she began to perform oral sex on him. She took him to her couch until there was a knock on the door and she had him again hide in the closet.
From inside the closet, Jeffrey watched as foul-mouthed Frank came in and sexually assaulted her, inhaling a gas as he did so. After Frank left, Jeffrey left the closet and attempted to comfort Dorothy. She believed him to be Don and requested him to hit her, but he refused. Just before leaving, he examined a photograph, finding Don and Donny to be Dorothy's husband and child, respectively.
The next night, Jeffrey filled in Sandy on the details of his visit to the apartment, and Sandy told him about a dream she had, where there was a world of darkness until robins brought light of love to it.
Jeffrey went back to the apartment and had a sexual encounter with Dorothy, then later went back to the Slow Club to watch her perform. There, he noticed Frank in the audience, holding a piece of blue fabric he had cut from Dorothy's robe.
Jeffrey soon began to tail Frank and his accomplices, and filled in Sandy on his investigation, naming two of the accomplices the "Yellow Man" and "Well-Dressed Man." Having discovered a criminal underground, Jeffrey wished to go further, despite Sandy's worries about him. The two express their attraction to each other with a kiss.
He returned to Dorothy's apartment, where they had another sexual encounter, and she requested him to hit her again. During his frustration, he ended up actually hitting her. As he left, he encountered Frank and his cronies, who took them for a joyride, stopping at This Is It to meet Ben, who had Dorothy's son. There, the men taunted and hit Jeffrey as they drank "to Frank's fuck." Frank then requested "candy-colored clown they call the sandman" and Ben began lip-synching to "In Dreams." The group soon left to continue the joyride.
After Jeffrey stopped Frank from again assaulting Dorothy, Booth and his gang took him out of the car and beat him up. He woke up in the morning, battered, and made his way home, haunted by the thought of hitting Dorothy.
He called Sandy to tell her that she could not be further involved, in order to keep her safe. He went downstairs for breakfast, refusing to talk about his injuries with his mother or aunt.
Jeffrey made his way to the police station and spotted the "Yellow Man" inside of an office, finding him to be Lt. T.R. Gordon. He later went to the Williams home, where he presented his findings to the Detective.
The following Friday, Jeffrey watered his yard and visited his father before going to the Williams' house to pick up Sandy for their planned date. Just after he arrived, Lt. Gordon showed up, and Detective Williams told Jeffrey to stay calm before sending the young couple on their way. He took Sandy to a party, where they expressed their love to one another on the dance floor as "Mysteries of Love" played.
On the way back to Sandy's home, they began to be chased. At first, Jeffrey believed the pursuer to be Frank, but it was Sandy's boyfriend, Mike, who wished to fight Jeffrey. However, the fight was soon stopped when a nude and dazed Dorothy appeared. They took her to the Williams' home to call an ambulance for her. There, Dorothy revealed their love affair to Sandy, who was disgusted, but quickly forgave Jeffrey. Dorothy also indicated that Don had been hurt in the head.
Jeffrey went back to the apartment, where he found Lt. Gordon bloodied, and having suffered from a crude lobotomy, standing near a dead Don Vallens, shot in the head. Radio chatter then came through Gordon's radio, indicating an assault on Frank's apartment. Jeffrey then declared that he would let the police find him on their own.
As Jeffrey went out on the stairwell, he saw the "Well-Dressed Man" approaching. He realized that it was actually Frank and escaped to the apartment. He took Gordon's radio and spoke to Williams. Upon realizing that Frank also had a radio, he indicated that he was in the bedroom, then made a dash for the closet just before Frank came inside. As Frank searched the bedroom, Jeffrey took Gordon's revolver, then watched as Frank fired around the apartment. When Booth finally opened the closet, Jeffrey shot him in the head, instantly killing him. Detective Williams arrived with Sandy right after, the Detective telling Jeffrey that it was all over.
Soon after, on a bright and sunny day, Jeffrey relaxed in his yard and opened his eyes to see a robin. Sandy called him in for lunch. On the way inside, he observed Detective Williams talking to his father, having made a substantial recovery since his stroke. When inside, Barbara pointed out a robin with a bug in its beak.
- In scenes deleted from the final cut of the film, Jeffrey has a girlfriend named Louise Wertham. During his time in Lumberton, she begins seeing someone else and eventually plans to get married. All traces of Louise were cut from the film.
- Kyle MacLachlan later played FBI Special Agent Dale Cooper in Twin Peaks, a television series co-created by David Lynch. MacLachlan considers Cooper to be a "grown-up" incarnation of Beaumont.