At its heart, The Last Starfighter is firmly grounded in the simple but compelling story of a young man, Alex Rogan (Lance Guest). With his mother, Jane (Barbara Bosson) and younger brother, Louis (Chris Herbert), Alex lives in a trailer court located in a ruggedly beautiful rural area. He is tired of his going-nowhere life at the trailer park, filled with onerous chores and responsibilities, and yearns to escape with his girlfriend, Maggie Gordon (Catherine Mary Stewart). One of his favorite outlets is playing a video game, and he is so good that one night he breaks the scoring record. He is happy for just a brief time before the weight of his hope and despair drags him back down to earth. Moping around that night, he is shocked when a strange star-car rolls into the trailer court. The driver, Centauri (Robert Preston), informs Alex that his skill at the game qualifies him to become a starfighter for real, in the service of the Star League. Intrigued at this prospect, Alex goes with Centauri back to the main Starfighter base on the planet of Rylos. Once their, Alex finds that Centauri is quite the rogue and con artist, having broken the rules to recruit him in the first place, and then failing to tell him that the Star League is engaged in a deadly war with the renegade Xur (Norman Snow) and his allies in the Ko-Dan armada.
This is not at all what Alex had in mind, and he forces Centauri to take him back to his less exiting but much safer life on Earth. He finds that a substitute, a "Beta unit" has been carrying on, literally in his shoes. Unknown to Alex, Xur and his minions carry out a devastating attack on the Starfighter base, killing the other budding starfighters. Alex gets only a brief respite before an alien "hitbeast" (Marc Alaimo) attempts to do Xur's bidding and kill the last starfighter.
Knowing that even more hit-beasts will follow, Alex knows that his only chance is to return to Rylos and become a true starfighter. He teams up with a reptilian pilot, Grig (Dan O'Herlihy), and reluctantly climbs aboard the last gun-star, an untested prototype. His first foray into combat is not entirely a success, as Alex still does not feel comfortable in his role, nearly giving up yet again. However, Grig boosts his morale with some inspirational speeches, and Alex recovers in time to leap into the furious climactic battle with the Xurian and Ko-Dan ships.
