After two years in detention, Kuniko returns to her village. Momoko is happy to have her home safe, but the arrival of a military assault force proves there are some who aren't pleased with Kuniko's newfound freedom.
Kuniko and her allies venture into the dangerous foliage outside their village, unaware that a recon party from Atlas is lurking nearby. Meanwhile, chaos strikes the carbon market after Karin unleashes Medusa.
After Miiko wins an opportunity to move to Atlas, Kuniko grows curious about what life is like within the city. Counterfeit work passes in hand, she leads a party on an infiltration mission - but not everything goes as planned.
Kuniko and Momoko travel to Akihabara to sell off a portion of Metal Age's carbon-rich graphite stockpile. Meanwhile, Karin attempts to learn the identity of a mysterious new player on the carbon market.
After spying on his comings and goings in Akihabara, Kuniko encounters Kunihito in public. With each suspicious of the other's motives and tactics, the tension between them eventually escalates to violence.
Karin and the Japanese government unleash a risky plan designed to lure Orochi into the open. When the program's location is revealed, Ryoko intercepts the information - and the U.S. military attacks.
After she's arrested by Atlas soldiers, Kuniko finds that things have changed for the worse at the detention center from which she was only recently released. There's a cruel new warden in charge now: Ryoko.
With her execution approaching, Kuniko receives a visit - and a care package - from Momoko. Later, as the firing squad takes aim, a daring escape attempt results in tragic consequences.
Already struggling with the guilt brought on by Momoko's capture, Kuniko must face an even darker pain when she and Takehiko make a gruesome discovery on the grounds of the prison.
With Momoko's fate weighing heavily on her shoulders, Kuniko fights to understand and confront her own destiny. Meanwhile, Ryoko exercises her newfound power as Prime Minister by launching an attack on Medusa.
Karin faces the reality of her lonely life after an encounter with a mysterious boy deep within the confines of her sanctuary. Elsewhere, Kuniko struggles to keep up with her new responsibilities as Metal Age's leader.
The Metal Age war against Atlas begins! Kuniko leads a risky aerial assault against the city, while riots erupt within Atlas's walls. As the battle rages, Karin attempts to profit from the situation.
Metal Age infiltrates Atlas, but confusion caused by the ever-changing scenery results in serious casualties. Later, Kuniko makes a shocking discovery about Atlas's past that will alter her life forever.
After Kunihito tells Kuniko about the numerous strange markings in the land around Atlas, Nagiko and Tarsian offer disturbing insight into the construction of the city - and the gruesome rituals undertaken to keep it standing.
Kuniko and Karin attempt to crash a satellite into the Marshall Islands in order to stop the rampaging Medusa. Meanwhile, Mikuni, shattered by the loss of Miiko, accepts an offer that might allow her to avenge her fallen friend.
When Mikuni's hunger for revenge and Ryoko's connection to Zeus endanger the world, Kuniko vows to stop them. Unfortunately, before she can take action, Kunihito appears with a gun - and he's got Kuniko in his sights.
Tarsian, Karin, and Nagiko work to prevent Medusa's plan of nuclear annihilation. Meanwhile, Kuniko rushes to Himiko's tomb to confront Ryoko and stop Mikuni from pulling the sacred spear.
Atlas teeters on the edge of collapse, threatening the lives of everyone inside. If the city's population is to be saved - and Japan is to rise from the ashes of her troubled past - Kuniko must battle the resurrected Himiko.