In a distant future, the immense blue humanoid creatures known as the Draags have transported humans, referred to as Oms, from Earth to their technologically sophisticated planet, Ygam. Within this advanced society, Draags view Oms as mere animals; some are kept as pets, while others roam wild and face periodic culling by the Draags to maintain population control. Despite their longer lifespans, the Draags reproduce infrequently.
The story begins when an Om mother is tragically tortured to death by three Draag children, leaving her infant orphaned. Thankfully, he is discovered by Master Sinh, a prominent Draag leader, alongside his daughter Tiwa. Tiwa, feeling a sense of compassion, takes the boy in, naming him Terr and treating him as a pet. Although she cares for him, her parents instruct her to keep him leashed with a collar that allows her to control his movements. Tiwa introduces Terr to her educational sessions, where she absorbs knowledge via a headset. Unbeknownst to her, a flaw in the collar enables Terr to acquire the same knowledge.
As the years pass, Tiwa enters her teenage years and begins her Draag meditation, a practice that allows her species to traverse through thoughts. Her growing independence leads to a dwindling interest in Terr, who matures into a young man brimming with Draag wisdom. Seizing his chance, he escapes into the wild, taking Tiwa's headset with him.
In the wilderness, Terr encounters a fierce female Om, who severs his collar and invites him to join her tribe in an abandoned Draag theme park filled with enigmatic creatures and surreal landscapes. There, Terr teaches them how to utilize the headset for gaining Draag knowledge and literacy, which earns him the respect required to engage in a duel to prove his worth. Armed with newfound literacy, they decipher a dire Draag announcement indicating an offensive plan to cleanse the park of Oms. As the purge commences, a brutal battle breaks out, with some Oms killed by the advancing Draag technology, while others manage to flee and link up with another tribe.
During their flight, they confront two Draag passers-by, successfully defeating one. They find temporary refuge in an abandoned Draag rocket facility, causing substantial dismay among Draag leaders. Over the ensuing years, more Oms join them, bolstered by Terr’s knowledge derived from the headset. They successfully replicate Draag technology and construct two rockets with hopes of escaping Ygam for the serene moon, known as the Fantastic Planet, to live free from Draag domination.
However, tragedy strikes as another large-scale Draag purge descends upon their depot, leading to more casualties among the Oms. In a desperate bid, Terr leads a group in the rockets to reach the Fantastic Planet. Once there, they discover vast statues used by Draag during meditation to connect with intergalactic beings in an extraordinary mating ritual essential for their survival. The Oms, seeking to protect their newfound freedom, destroy several of these statues, thereby endangering the existence of the Draags.
Faced with extinction, the Draags are compelled to negotiate a peace treaty, halting the genocide of Oms on Ygam. In a mutual agreement, the Oms consent to vacate the Fantastic Planet in exchange for the establishment of an artificial satellite in orbit around Ygam, granting them a new home. This pivotal decision ushers in a new era characterized by harmonious coexistence between the two species, allowing them to benefit from each other's unique perspectives and ways of life.
