Bane/Smith and Neo find themselves in a state of unconsciousness, yet their circumstances couldn't be more different. While Bane is merely asleep, Neo's neural patterns resemble those of individuals connected to the Matrix. Amidst the despair following the destruction of the Nebuchadnezzar and the revelation regarding the Prophecy at the conclusion of the previous film, Morpheus (Laurence Fishburne) embarks on a quest to locate Neo within the Matrix, despite Neo not being connected. In actuality, Neo is ensnared in a limbo known as Mobil Avenue, a subway station serving as a transition zone between the Matrix and the Source, the central hub of the Machines.
Within this station, Neo encounters a peculiar ‘family’ of programs. The young girl, Sati, confides in him that her father believes Neo doesn’t belong in this realm. Her father explains that Mobil Avenue is governed by a program called The Trainman, who is an exile fully devoted to the Merovingian. As Neo attempts to board a train with Sati’s family, The Trainman obstructs him, asserting his authority by stating, “I make the rules down here.”
Meanwhile, Seraph reaches out to Morpheus and Trinity on behalf of the Oracle, who is now in a new “shell.” She discloses Neo's precarious situation in Mobil Avenue. Determined to rescue him, Morpheus, Trinity, and Seraph chase after The Trainman, but he escapes. Their last recourse is to venture into the chaos of Club Hel to confront the Merovingian for Neo’s freedom. They engage in a fierce battle through the club, battling guards who defy gravity. Armed with two guns each, they force their way past the guards and access the elevator, determined to reach The Merovingian.
Upon entering the grand dance hall, the Merovingian, with a mix of disdain and respect, instructs them to relinquish their weapons for an audience. Demanding “the eyes of the Oracle” in exchange for Neo, tensions reach a boiling point when Trinity triggers a Mexican standoff, compelling the Merovingian to concede and release Neo.
In Mobil Ave, Neo's attempts to escape lead him back into the station. Later, Trinity arrives to free him. Guided by troubling visions of the Machine City, Neo seeks an audience with the Oracle one last time. She reveals that as the One, his connection to the Source has granted him all his extraordinary abilities within and outside of the Matrix. She warns Neo of Smith, characterizing him as his "exact opposite" and emphasizing that Smith now poses a monumental threat not just to the Matrix but to the Source and Machine City itself. The Oracle ominously states, “The war is about to end... one way or another.”
After Neo's departure, a surge of Smith clones erupts at the Oracle’s location. The original Smith confronts Seraph and Sati, assimilating the Oracle and acquiring her foresight, illustrating the escalating danger looming over the Matrix.
In the real world, the surviving crews, including the Nebuchadnezzar and Mjolnir (also known as "the Hammer"), locate Niobe’s inactive ship, the Logos, and wake Bane, who feigns amnesia regarding prior events. Neo determines that he needs a ship to head to the Machine City, despite lacking clarification on his motives. While Roland, captain of the Mjolnir, denies him this request, Niobe, influenced by the Oracle’s counsel from the game Enter The Matrix, ultimately allows Neo to commandeer the Logos, much to Roland’s bewilderment. As a show of solidarity, Trinity opts to accompany him.
The two crews strategize to navigate Zion while evading the Sentinel army, with the Mjolnir initially piloted by Niobe venturing through treacherous service tunnels. Along their journey, they soon discover that Bane has hidden aboard the Logos, having already committed murder aboard the Mjolnir. Without a chance to inform Trinity and Neo, Bane ambushes Trinity, taking her hostage. During their confrontation, Bane uncovers himself as a manifestation of Smith. Despite Neo becoming blinded in the fray, he perceives Smith’s essence within Bane, leading him to defeat Bane and free Trinity.
Flying the Logos towards the Machine City, Neo and Trinity witness sprawling harvesting fields filled with humans producing energy for the city. They soon encounter resistance from the city’s defenses, but with Neo's extraordinary powers, he annihilates incoming threats. However, the relentless Sentinels overpower them, forcing the ship into a tempest. In a moment of fleeting beauty, Trinity glimpses the sunlight above the clouds before the ship crashes, fatally wounding her.
In a climactic resolution, Neo reaches the Machine City and negotiates with the machines, embodied by the Deus Ex Machina. He warns them of Smith's growing power, asserting that he will halt Smith’s onslaught if they agree to a ceasefire with Zion. Both parties, recognizing the necessity of collaboration, proceed to confront Smith within the Matrix. Engaging in an epic showdown filled with breathtaking battles across the city, Neo and Smith unravel each other until the intensity reaches a pivotal climax.
As Neo rallies against the odds, he cleverly baits Smith into assimilating him, leading to unexpected consequences. His inner struggle culminates in a battle of wills, where the light of Neo's essence begins to obliterate Smith's clones from within, restoring balance as the Oracle regains her powers. With human lives saved, Neo sacrifices himself, courageously unplugged from the Matrix, symbolizing a newfound hope and the potential for peace between humans and machines.
In the final moments of the film, the Architect converses with the Oracle, discussing the future of humanity in the Matrix. As the dawn breaks in this reimagined world, a vibrant landscape flourishes, signaling a transformed reality that stands bereft of the oppressive green tint, suggesting a peaceful coexistence on the horizon.
