In the seemingly bright and beautiful town of Lumberton, North Carolina, Tom Beaumont tends his yard when he suddenly suffers a massive stroke. Because of this, his son Jeffrey returns home from college. He goes to the hospital, where his father cries, unable to speak.
Jeffrey makes his way to a vacant lot, where he throws stones until he finds a decomposing severed ear. He places it in a paper bag and takes it to Detective John Williams of the Lumberton Police. The coroner examines the ear and determines that the owner could still be alive and that it was cut off with scissors. A search of the field the ear was found in then takes place, Jeffrey observing.
He later went out for a walk, stopping at the Williams home to see the Detective Williams about the case. However, the Detective tells him he cannot release any information about it. Shortly after leaving, Jeffrey encounters the Williams' daughter, Sandy. She tells him that she has overheard details about a singer somehow related to the severed ear.
Sandy shows Jeffrey to the apartment building where the singer lived, located on Lincoln Street, where Jeffrey's aunt Barbara warned him to not go. They turn back and Jeffrey catches up on his old hometown.
Jeffrey picks up Sandy from school the next day, taking her to Arlene's Diner. There, he discusses with her his plan to get into the singer's apartment, posing as a pest control worker and her as a Jehovah's Witness.
Learning the singer's name to be Dorothy Vallens, Jeffrey makes his way up to her apartment, where he sprays from a bug-spraying rig and steals a key when the singer left to answer the door, where there is a man in a yellow suit.
Sandy cancels her date with her boyfriend, Mike in order to continue her investigation with Jeffrey at the Slow Club, where Vallens sings "Blue Velvet" and "Blue Star." After the performance, they make their way to her apartment again so that Jeffrey can sneak in. They agree to have Sandy warn him of her arrival by honking the horn. However, Jeffrey does not hear this due to flushing a toilet.
Upon realizing that someone else was entering the apartment, Jeffrey hides in a closet, watching as Dorothy takes a call from Frank Booth, who allows her to speak to her husband, who she asks of the well-being of their son. After the phone call, Jeffrey accidentally knocks down a coat hanger, causing Dorothy to notice him. She threatens him with a knife, believing him to be a voyeur. She has him undress at knifepoint and begins to perform oral sex. She takes him to the couch, but they are interrupted by a knock on the door.
After hiding Jeffrey back in the closet, Dorothy answers the door. Frank Booth comes in and sexually assaults her (all while inhaling an unspecified gas) as Jeffrey watches from the closet. After the attack, Jeffrey leaves the closet and tries to comfort Dorothy. She requests him to hit her, but he refuses.
The following night, Jeffrey fills in Sandy on the details of his visit. She then tells him of a dream she had where a world of darkness was finally given light by robins that represented love.
Jeffrey goes back to the apartment where he has a sexual encounter with Dorothy. During another visit to the Slow Club, Jeffrey notices that Frank is present at the performance, holding a piece of fabric he cut from Dorothy's robe.
Jeffrey begins to tail Frank and his accomplices, naming two of them "Yellow Man" and "Well-Dressed Man." He discovers a criminal underground but is unsure of what to do with the information. They then share a kiss, confirming their attraction to each other.
Beaumont returns to Dorothy's apartment, where he ends up hitting her during a sexual encounter. As Jeffrey leaves, they encounter Frank, who takes them for a joyride, stopping at This Is It to visit Ben, who possesses Dorothy's child. They antagonize Jeffrey and drink to "Frank's fuck." Dorothy is then allowed to see Donny as Ben lip-synchs "In Dreams" for Frank before the joyride continues.
They go out to the country, where Frank inhales the gas he used in the assault and begins to start on Dorothy again, but when Jeffrey punches him, Frank and his gang take Jeffrey out of the car and beat him up, despite Dorothy's protests, all while once again listening to "In Dreams."
Jeffrey wakes up, dirty and bruised. He returns home, where he is disturbed by the thought of hitting Dorothy. He calls Sandy and tells her that he will leave her out of the rest of his investigation, so as to keep her safe.
Upon visiting the police station, Jeffrey spots Frank's accomplice the "Yellow Man," who is actually Lt. T.R. Gordon and Jeffrey takes his information to Detective Williams.
The following Friday, Jeffrey waters the yard and visits his father before picking up Sandy for their planned date. Just after Jeffrey arrives, Gordon does to meet Detective Williams, who tells Jeffrey to stay calm before sending he and Sandy on their way.
Jeffrey and Sandy go to a party, where they express their love to each other on the dance floor as "Mysteries of Love" plays. After the party, Jeffrey drives Sandy home, but they are chased by Sandy's boyfriend Mike. Mike challenges Jeffrey to a fight, but it is stopped when a nude and dazed Dorothy emerges. She is taken to the Williams' home, where an ambulance is called for her. Dorothy reveals to Sandy her's and Jeffrey's relationship, but Sandy forgives Jeffrey and agrees to have her father send police to Dorothy's apartment.
Jeffrey goes to the apartment, where he finds Lt. Gordon bloodied and standing, having suffered from a sort of lobotomy, and a dead Don Vallens, having been shot in the head. Jeffrey hears Gordon's radio chattering as an assault on Frank's apartment building takes place. He declares that he will let the police find Frank on their own and he leaves the apartment.
However, as he leaves the building, he sees the "Well-Dressed Man" from the stairwell and realizes that he is actually Frank in disguise. He quickly makes his way back to the apartment and takes Gordon's radio. He goes to the bedroom and speaks to Williams. Realizing that Frank also has a radio, he says that he is in the bedroom, then dashes to the closet. As Frank searches and shoots in the bedroom, Jeffrey quickly grabs Gordon's revolver and retreats back into the closet, waiting as Frank begins randomly firing around the apartment. When Frank finally opened the closet, Jeffrey fired a shot into his head, immediately killing him. Detective Williams and Sandy then arrive.
Soon after, on a bright and sunny day, Sandy calls Jeffrey in for lunch. On his way inside, Jeffrey observes Detective Williams speaking to his father, who has recovered substantially. When inside, Barbara points out to them a robin with a bug gripped in its beak.
Dorothy is then happily reunited with her young son.
- A man playing guitar asks a man about a dog pursuing a rabbit. The second man's barking then becomes within the rhythm of the guitar playing as topless women dance. Frank and his gang then come in with Jeffrey and Dorothy. There, Frank chases down a man named Willard, who had apparently torn Frank's coat and made him lose a piece of blue velvet. Frank threatens him with a "love letter" and pushes one of the topless women next to her before leaving to the next room.
- A woman calls to a man named Greg, telling him that Billy is waiting for his teddy bear. She looks outside to see her son Billy standing over Tom Beaumont just after his stroke.
- At a college party, a student is looking for Jeffrey, as he has received a phone call from his mother. He is then seen watching a sexual assault take place until he tells the man to leave the girl alone. He goes to answer the phone, and his mother requests that he return home for good following his father's stroke.
- In the morning, Jeffrey says goodbye to his friends and his girlfriend, Louise Wertham. He and Louise kiss and the scene cuts to a plane taxing, followed by his mother and aunt Barbara driving him home, explaining what happened to his father. After arriving home, Jeffrey goes up to his room.
- Mrs. Beaumont and Aunt Barbara eat breakfast, then call Jeffrey down. He comes down and discusses his plan to see his father, warning him not to tell his father that he had dropped out of school to be there.
- Jeffrey calls Louise, who has been asked to an event by a male. After a brief talk, he hangs up and thinks.
- Mrs. Beaumont and Aunt Barbara sing "Oh My Darling, Clementine" as they wash dishes.
- Jeffrey goes to see Detective Williams, who is currently absent, so he talks to Mrs. Williams over a coffee and a piece of cake. Sandy briefly comes in with Mike just before John arrives and invites Jeffrey to his study to discuss the case, leaving Mrs. Williams alone.
- Dr. Gynde injects Mrs. Beaumont and encourages her to keep her stress levels low. Jeffrey comes in and questions the doctor how his whole family is sick, then asks to use the car for the evening. Jeffrey picks up Sandy and they go over their plan to see Dorothy perform, then go back to her apartment. They arrive at the Slow Club and request a table in the back. They watch as a dog eats from a bowl onstage and ask when Dorothy would begin to perform. As they wait, a man performs "Beautiful Dreamer" as another man performs stand-up comedy.
- Jeffrey comes home late, his mother waiting, worried about what he had been up to.
- Jeffrey calls Louise but learns that she is getting married. He suggests that if things don't work out, she should go into comedy. He then hangs up.
- Aunt Barbara tells Jeffrey that she believes there are termites in the house. Jeffrey then has dinner with the Williams' and Mike while Barbara checks the Beaumont home for termites, finding one.
- Sandy, Mike, and Jeffrey watch television until Mrs. Williams offers blueberry pie and ice cream, which Sandy and Jeffrey accept, though Mike is disinterested in both dessert and television. He excuses himself and Sandy asks Jeffrey what he has learned during his investigation up to that point. Mike asks to speak with Sandy outside as Mrs. Williams brings coffee to Jeffrey. Detective Williams invites Jeffrey to his study to see some photographs from the vacant lot the ear was found in. Sandy then asks for the car and offers to take Jeffrey to Dairy Queen. They go out to the car and discuss the investigation.
- Jeffrey wishes to kiss Sandy goodnight when she drops him off at home, but they agree that it would be best if he did not. He goes inside and finds a note from Barbara, confirming the presence of termites in the house.
- Jeffrey calls Dorothy's apartment and Frank picks up. Both are silent until Jeffrey says "Hello?" and Frank responds, "Speak to me, fucker."
- Jeffrey follows Frank to Dorothy's apartment. He waits in his car until Frank comes back and drives away. He goes into Dorothy's apartment but hides when the "Yellow Man" comes for a visit, wondering why he cannot use her for sexual favors like Frank does. When he leaves, Dorothy leads Jeffrey down the apartment floor's hallway and up to the roof, wishing to commit suicide. She throws one of her shoes off the roof and peers over the edge, and when she nearly falls, Jeffrey stops her and they kiss.
- Jeffrey goes up the stairs to the apartment and encounters an old woman who says "it's about time you came."
"Newly Discovered Lost Footage"
- Woman in Pool Room - Gail Moore
- Bartender - Gail Sanchez
- Willard - David Parker
- Gregg's Mother - Debra Shuckman
- Dancing College Student - William Finger
- Louise - Megan Mullally
- College Boy - Jody Ray Parker
- Rape Victim - Farah Jade Roberts
- Lipstick Girl (TV) - Jennifer Lynch
- Waiter - Graham F. Smith
- Comic - Pat Miller
- Drummer - Nic Ponos
- Old Lady - Nell Kallfelz