Teenager Alex Rogan lives at the Starlite Starbrite trailer park with his mother, Jane, and brother, Louis. In addition to her job as a waitress in a nearby town, Jane serves as the park’s manager, and Alex helps with maintenance. The boy spends his free time playing an arcade game, “Starfighter,” which simulates space battles, at the park’s convenience store. One day, Alex stays behind to work while his friends go to a lake for a picnic, but he reminds them that while they stay home to attend City College, he is destined for bigger things. Later, Alex is jealous when his girlfriend, Maggie Gordon, gets a ride home from another boy. Alex breaks the Starfighter record to the cheers of his neighbors. Afterward, Alex assures Maggie he will return for her once he is settled at college. When Jane arrives home, she informs Alex he did not get a student loan and will be attending City College with his friends. Sitting outside, Alex witnesses a futuristic-looking “Star Car” pull up to the park. The driver, Centauri, introduces himself as the inventor of Starfighter and wants to meet the person who broke the game’s record. Centauri invites Alex to go for a ride and discuss something of the utmost importance, but will not reveal their destination. Soon, Alex realizes he is in a rocket ship and Centauri is an alien. In another part of the universe, they land on the planet Rylos, which Alex recognizes from the video game. Other than Centauri, no one speaks English and an electronic translator is attached to his collar, allowing him to understand what the others say. Alex learns he has been recruited by the Star League to be a Starfighter, and defend the Frontier against a rebel named Xur and the Ko-Dan Armada. As Alex explains to Centauri and a pilot named Grig that he does not want be part of their war, Xur appears as a hologram to threaten his father, Ambassador Enduran, the commander of the Starfighters. Reluctantly, Centauri returns Alex to Earth, but gives him a “communal crystal” to signal if he changes his mind. Meanwhile, Xur orders an attack on the Starfighter base, and a traitor inside the base sabotages its defenses. Back on Earth, Maggie slaps Alex and informs him she is no longer speaking to him. Alex realizes that Centauri left a “simuloid,” called Beta, a robotic replica to take his place while he was away. A hitchhiker enters the trailer park, but is revealed to be an alien when he passes near the Starfighter arcade game. When Alex goes outside to summon Centauri to retrieve Beta, the alien attacks him. Centauri arrives and wounds the alien, explaining it is a Xanodan, an assassin sent by Xur to kill Alex. The Xanodan fires on Centauri, wounding him, but is killed in the exchange. Centauri warns Alex that Xur will continue to send Xanodans after him. The only way to protect Earth is to return to Rylos and be a Starfighter. Alex acquiesces, but Centauri apparently dies from his injuries on their arrival on Rylos. Alex is the last remaining Starfighter and a lizard-like being named Grig trains him to be a gunner on a Gunstar warship. Grig tests Alex in a skirmish with a Xurian warship. Afterward, Alex claims he is not a true Starfighter, and he and Grig share photographs of their families. Later, Alex devises a plan to attack the Ko-Dan Armada, and realizes he might be a Starfighter after all. On Earth, Beta attempts to maintain the pretense of being Alex, but his odd behavior raises Maggie’s suspicions. Beta tries to explain he is not really Alex, but she does not believe him until a Xanodan, disguised as a police officer, wounds Beta, exposing his circuitry. Beta tells Maggie he must kill the Xanodan so that Xur does not learn Alex is in space. The simuloid rams a stolen truck into the Xanodan’s police car, and Xur believes Alex, the last remaining Starfighter, has been killed. Back in space, Alex and Grig enact their attack plan on the Armada. Realizing Alex is alive, Lord Kril relieves Xur of his command, and prepares to defend against the Gunstar. Xur flees in an escape pod as Alex uses his Starfighter abilities to defeat the Armada. The command ship attacks while the Gunstar recharges its power supply, but Grig evades fire. Alex neutralizes the command ship and the vessel is sucked into a moon’s gravitational pull and explodes. Following the battle, Ambassador Enduran invites Alex to remain to help rebuild the Star League with the help of an old friend. Centauri steps forward and explains that he did not die, but simply went dormant while his body repaired itself. As he contemplates Enduran’s offer, Alex receives a hero’s welcome from the citizens of Rylos. Later, on Earth, as Maggie wonders how she will explain the situation to Alex’s mother, the Gunstar lands and Alex emerges in his Starfighter uniform. When he kisses Maggie, she knows it is really him. The residents of the trailer park gather around the spacecraft and Alex introduces them to Grig. Alex invites Maggie to join him on Rylos. She is afraid to leave home, but changes her mind when she realizes Alex is really leaving. As the Gunstar blasts off, Louis begins playing the Starfighter game, hoping to one day emulate his brother.