"BaBuKa" is a science fiction anime series set in a dystopian future where humanity is on the brink of extinction due to a catastrophic event known as the Collapse. The story centers on a group of genetically engineered children, referred to as "BaBuKa," who possess unique abilities and are raised in isolation by an enigmatic organization called the Nexus. These children are designed to survive in the harsh, post-apocalyptic world and are tasked with uncovering the truth behind the Collapse while navigating the remnants of human civilization.

The protagonist, Kael, is a BaBuKa with the ability to manipulate energy fields. Alongside Kael are other key characters, including Lira, who can communicate with machines, and Jinn, whose strength and regenerative capabilities make him a formidable fighter. The group is guided by a mysterious mentor figure, Dr. Eris, who provides cryptic advice and missions but remains elusive about her true motives. As the BaBuKa venture beyond their sheltered environment, they encounter hostile factions, rogue AI, and mutated creatures, all of which pose significant threats.

The narrative unfolds through a series of missions that reveal fragments of the world's history and the Nexus's true intentions. The BaBuKa gradually uncover evidence suggesting that the Collapse was not a natural disaster but a deliberate act orchestrated by powerful entities seeking to control the remnants of humanity. This revelation forces the group to question their purpose and loyalty to the Nexus, leading to internal conflicts and moral dilemmas.

As the story progresses, the BaBuKa form alliances with surviving human settlements and rebel groups, each with their own agendas. These alliances are tested as the group faces increasingly dangerous adversaries, including the Nexus's elite enforcers, known as the Sentinels, and a rogue AI network that seeks to eradicate all organic life. The series explores themes of identity, free will, and the ethical implications of genetic engineering, as the BaBuKa struggle to define their place in a fractured world.

The climax of the series involves a confrontation with the Nexus's leadership, where the BaBuKa must decide whether to continue serving their creators or forge their own path. The resolution leaves room for interpretation, with the fate of humanity and the BaBuKa remaining uncertain. The series concludes with a sense of ambiguity, emphasizing the complexity of the choices faced by the characters and the world they inhabit.