Following the tragic events of his father's genetic transmutation, Martin Brundle is born to Veronica Quaife, who dies during his accelerated birth. Raised initially by Veronica's friend, Martin is a child prodigy whose biological age far outpaces his chronological one due to dormant teleportation-pod genes. By age five, he has the physical body of a mature adult. Recognizing the boy's genius and physical vulnerability, corporate executive Bartok adopts Martin, housing him within Bartok Industries. Driven by a secretive profit-motivated agenda, Bartok tasks Martin with finishing his father's failed teleportation project. Martin desperately desires a normal life and a cure for his genetic condition, which threatens to trigger a monstrous transformation, but he hits a dead end. His only solace is found in Beth Logan, a compassionate
computer programmer working at the facility, with whom he quickly falls in love. Martin manages to successfully teleport objects, but the pod’s computer system consistently fails to decipher human genetic coding, resulting in horrific deformities in test subjects. Secretly, Martin creates a secluded sanctuary for a stray dog he subjected to the teleportation process, monitoring the loyal creature despite its mutating agony. As Martin's health deteriorates, he discovers that Bartok has been monitoring him closely all along, viewing him merely as expensive property rather than a human being. Realizing he is
running out of time, Martin injects himself into the teleportation pods, hoping the machine can purge the remaining insect DNA from his system. Instead, the pod identifies his mutated cells as a baseline and initiates a horrific metamorphosis. Martin transforms into a colossal, ravenous humanoid insect creature, driven by instinct and a desperate need for survival. Now a terrifying monster, Martin escapes his containment, wreaking bloody vengeance upon the security guards and researchers who tormented him, including the deceitful Bartok. He tracks down Beth, but rather than harming her, he communicates through his remaining humanity, urging her to help him enact a final, brilliant plan. Beth lures Bartok into the teleportation laboratory, where Martin, now barely recognizable, ambushes the corrupt CEO. With Beth's help operating the machinery, Martin forces Bartok into the pod alongside his mutated form, initiating a genetic reversal sequence. The machine successfully purges the insect DNA from Martin, transferring it instead into Bartok. As the facility crumbles around them, Martin emerges completely human once again, reunited with Beth. Meanwhile, the mutated Bartok is left trapped within a containment cell, a grotesque testament to corporate greed and genetic hubris.