John Carter: The War for the Barum (2025) expands the world of Barsoom with a sweeping adventure that reconnects John Carter to the planet he once fought to save. After years of living quietly on Earth, Carter is suddenly pulled back to Mars when Dejah Thoris sends a desperate telepathic message. A new and mysterious force known as the Barum—an ancient subterranean civilization long thought extinct—has risen to wage war on the surface nations, threatening to collapse the fragile unity Carter helped establish.
Upon his return, Carter finds Barsoom in turmoil. The once-vibrant cities of Helium and Zodanga stand on the brink of annihilation as colossal machines erupt from beneath the red sands. These machines, powered by ancient Barum energy cores, tear through the desert with unstoppable force. Dejah reveals that the Barum blame the surface races for stealing their resources centuries ago, and now they intend to reclaim the planet by force. Carter must navigate both political tensions and the brewing war to prevent Barsoom from falling into chaos.
As Carter journeys into the heart of the desert, he encounters Thark warriors preparing for battle—led by his old ally Tars Tarkas, who reveals that the Barum are not merely warriors but possess advanced technology that dwarfs anything seen on Barsoom. Their leader, a calculating warlord named Vharok, seeks to reshape the entire planet by releasing a massive energy surge capable of wiping out all surface life. Carter realizes he must travel deep underground to confront this threat directly.
The expedition leads Carter, Dejah, and a small alliance of Tharks and Helium soldiers into vast caverns glowing with otherworldly energy. There they discover the truth: the Barum were once protectors of Barsoom’s core, safeguarding the planet’s lifeforce until centuries of war and exploitation drove them into the shadows. Vharok’s vengeance stems from a history of betrayal, and his rage has twisted the Barum into a militant empire.
As tensions rise, Carter attempts to reason with Vharok, only to find that diplomacy is impossible. A massive battle erupts beneath the planet’s surface, with Carter fighting through labyrinths of machinery and ancient ruins to reach the central energy chamber. In a desperate final struggle, he manages to stop Vharok by destroying the unstable core, preventing the annihilation of Barsoom but causing the Barum empire to collapse.
The film concludes with Carter emerging back into the sunlight as Barsoom stabilizes. Though victorious, he knows the planet’s future remains uncertain. Yet he stands ready—champion of two worlds, bound by duty to both.
