In a room at a university campus, white and black students argue about an impending student strike. Mark leaves the meeting after declaring he is
> "willing to die, but not of boredom" for the cause, a remark that draws sharp criticism from the young white radicals. After a mass arrest at the campus protest, Mark visits a police station hoping to bail his roommate out of jail. He is told to wait but goes to the lock-up area, asks about bail for his roommate, is rebuffed, and ends up being arrested himself. He gives his name as Karl Marx, which a duty officer types as "Carl Marx." After he is released from jail, Mark and another friend buy firearms from a Los Angeles gun shop, saying they need them for "self-defense" to "protect our women."
In a downtown Los Angeles office building, the real estate executive Lee Allen reviews a television commercial for Sunny Dunes, a new resort-like development in the desert. The ad features casually dressed, smiling mannequins instead of actors, and the scene is paired with a discussion about the rapid growth of the greater Los Angeles area as two men drive through crowded streets.
Mark goes to a bloody campus confrontation between students and police. Some students are tear-gassed and at least one is shot. As Mark reaches for a gun in his boot, a Los Angeles policeman is seen being fatally shot, though it is unclear who fired the fatal shot. Mark flees the campus and rides a city bus to suburban Hawthorne, California where, after failing to buy a sandwich on credit from a local blue-collar delicatessen, he walks to Hawthorne Municipal Airport, steals a Cessna 210 aircraft and flies into the desert.
Meanwhile, Daria is driving across the desert toward Phoenix to meet her boss, who is implied to be more than just a colleague. Along the way she is searching for a man who works with "emotionally disturbed" children from Los Angeles. She finds the young boys near a roadhouse in the Mojave Desert, but they tease, taunt, and grab at her, boldly asking for "a piece of ass," to which she replies, "Are you sure you'd know what to do with it?"
Daria flees in her car. While filling its radiator with water, she is spied from the air by Mark, who buzzes her car and then flies only 15 feet over her as she lies face down in the sand. He throws a T-shirt out of the window of the aircraft for her to pick up. Daria goes from upset to curious and smiling during this sequence.
They later meet at the desert shack of an old man, where Mark asks her for a lift so he can buy gasoline for the aircraft. The two then wander to Zabriskie Point, where they make love. As they begin, other unidentified young naked people are shown playing sexually on the ground, their wild games sending up thick clouds of white dust from the desert floor.
Later, a California Highway Patrol officer suspiciously questions Daria. Hidden behind a portable toilet meant for tourists, Mark takes aim at the policeman, but Daria stands between the two to block him, apparently saving the policeman's life before he drives away. Daria asks Mark if he was the one who killed the cop in Los Angeles. He states that he wanted to, but someone else shot the officer first and that he "never got off a shot."
Returning to the stolen aircraft, they paint it with politically charged slogans and psychedelic colors. Daria pleads with Mark to ride with her and leave the aircraft, but Mark is intent on returning with it and the risks that it entails. He flies back to Los Angeles and lands the plane at the airport in Hawthorne. The police (along with some radio and television reporters) are waiting for him, and patrol cars chase the aircraft down the runway. Instead of stopping, Mark tries to turn the taxiing aircraft around across the grass and is shot dead by one of the policemen.
Daria learns about Mark's death on the car radio. She drives to Lee's lavish desert home, set high on a rock outcropping near Phoenix, Arizona, where she sees three affluent women sunning themselves and chatting by the swimming pool. She grieves for Mark by drenching herself in the house's architectural waterfall. Lee is deeply immersed in a business meeting having to do with the complex and financially risky Sunny Dunes development. Taking a break, he spots Daria in the house and happily greets her. She goes downstairs alone and finds the guest room that has been set aside for her, but after briefly opening the door, she shuts it again.
Seeing a young Native American housekeeper in the hallway, Daria leaves silently. She drives off, but stops to get out of the car and look back at the house, her own imagination repeatedly picturing it blown apart in billows of orange flame and scattered household items.
