In 1977, the Voyager 2 deep space probe was launched, carrying a gold phonographic disk that contained messages of peace and an invitation to extraterrestrial visitors to come to Earth. An alien spaceship intercepts the Voyager probe and sends a small scout vessel in response, aiming to establish first contact. However, the mission is met with hostility when the spacecraft is shot down by the US government. The craft crashes in Chequamegon Bay, Wisconsin, where a blue ball of energy emerges from the wreckage. This alien finds its way to the home of the recently widowed Jenny Hayden. As it explores her belongings, it discovers a lock of hair belonging to her late husband, Scott, in a photo album, and uses this to clone a new human body.
Shocked and confused, Jenny watches as the alien takes on the form of her husband. This Starman (portrayed by Jeff Bridges) possesses seven small silver spheres, which allow him to perform miraculous feats. He uses one of these spheres to send an urgent message to his people, informing them of his predicament and his intentions to rendezvous at "Landing Area One" in Arizona, just three days away. To navigate the journey, he creates a holographic map of the United States, compelling the bewildered Jenny to help him reach his destination.
Despite her fear and initial hostility, Jenny finds herself drawn into the Starman's mission. After a series of misunderstandings and a desperate plea for help, wherein she attempts to shoot him, the Starman disarms the situation, reassuring her he means no harm. As they travel together, the Starman gradually learns to communicate by assimilating knowledge from the Voyager disk, and Jenny introduces him to the nuances of human culture and emotions.
Haunted by grief but motivated by compassion, Jenny teaches Starman basic human skills such as driving and using credit cards, all while he explains to her the urgency of his mission. At one point while dining at a small café, Jenny tries to convey the concept of love to the Starman, who continues to astonish her with his abilities, including reviving a dead deer, which deepens her resolve to assist him.
Unbeknownst to them, the US army, led by the merciless NSA Chief George Fox and assisted by the empathetic SETI scientist Mark Shermin, is hot on their trail after discovering the crash site of the Starman's ship. As their journey unfolds, the couple must confront the pursuit of the authorities and navigate the challenges posed by fear and misunderstanding.
In a tense showdown, Jenny suffers a gunshot wound from pursuing officers. In a moment of desperation, Starman uses one of his last spheres to heal her, demonstrating the depth of his connection to her. As he continues on without her, determined to reach Arizona alone, Jenny awakens and embarks on a journey to reunite with him, unaware of the dangers still lurking.
Through a remarkable series of events, they manage to escape capture—hitching rides from unsuspecting drivers, navigating through a chaotic traffic jam, and ultimately finding refuge in a boxcar on a train as they grow even closer. It becomes clear that the Starman has bestowed upon Jenny a miraculous gift—a child who will be a combination of her late husband and himself, ready to inherit knowledge and insight.
Their journey takes an unexpected turn as they find themselves in Las Vegas, where Starman wins a substantial jackpot by manipulating a slot machine. They use their winnings to purchase a new vehicle to complete their fateful drive toward Barringer Crater in Arizona, where their destiny awaits.
As the couple's journey nears its end, they experience profound emotional transformations, culminating in poignant conversations about love, legacy, and the universe. However, the government agents are closing in, forcing them into a cafe in Winslow, where Starman shares with Shermin that humans often reveal their true strength in moments of adversity.
When they finally reach the crater beneath alien craft, Jenny is met with devastating news that she must let go. With armies closing in, the aliens arrive and rejuvenate the Starman. He shares a final moment with Jenny, urging her to pass on his message to their child before departing for his world. Their last kiss is an emotional farewell as Jenny watches, heartbroken yet filled with hope, as the mothership rises into the sky, carrying the Starman away into the unknown.
