In the distant future, humanity has been driven to near-extinction by giant beasts known as Klaxosaurs, forcing the surviving humans to take refuge in massive fortress cities called Plantations. Children raised here are trained to pilot giant mechas known as FranXX—the only weapons known to be effective against the Klaxosaurs—in boy-girl pairs. Bred for the sole purpose of piloting these machines, these children know nothing of the outside world and are only able to prove their existence by defending their race. Hiro, an aspiring FranXX pilot, has lost his motivation and self-confidence after failing an aptitude test. Skipping out on his class' graduation ceremony, Hiro retreats to a forest lake, where he encounters a mysterious girl with two horns growing out of her head. She introduces herself by her codename Zero Two, which is known to belong to an infamous FranXX pilot known as the "Partner Killer." Before Hiro can digest the encounter, the Plantation is rocked by a sudden Klaxosaur attack. Zero Two engages the creature in her FranXX, but it is heavily damaged in the skirmish and crashes near Hiro. Finding her partner dead, Zero Two invites Hiro to pilot the mecha with her, and the duo easily defeats the Klaxosaur in the ensuing fight. With a new partner by his side, Hiro has been given a chance at redemption for his past failures, but at what cost? [Written by MAL Rewrite]

The Abyss—a gaping chasm stretching down into the depths of the earth, filled with mysterious creatures and relics from a time long past. How did it come to be? What lies at the bottom? Countless brave individuals, known as Divers, have sought to solve these mysteries of the Abyss, fearlessly descending into its darkest realms. The best and bravest of the Divers, the White Whistles, are hailed as legends by those who remain on the surface. Riko, daughter of the missing White Whistle Lyza the Annihilator, aspires to become like her mother and explore the furthest reaches of the Abyss. However, just a novice Red Whistle herself, she is only permitted to roam its most upper layer. Even so, Riko has a chance encounter with a mysterious robot with the appearance of an ordinary young boy. She comes to name him Reg, and he has no recollection of the events preceding his discovery. Certain that the technology to create Reg must come from deep within the Abyss, the two decide to venture forth into the chasm to recover his memories and see the bottom of the great pit with their own eyes. However, they know not of the harsh reality that is the true existence of the Abyss. [Written by MAL Rewrite]

Aslan Jade Callenreese, known as Ash Lynx, was a runaway picked off the streets of New York City and raised by the infamous godfather of the mafia, Dino Golzine. Now 17 years old and the boss of his own gang, Ash begins investigating the mysterious "Banana Fish"—the same two words his older brother, Griffin, has muttered since his return from the Iraq War. However, his inquiries are hindered when Dino sends his men after Ash at an underground bar he uses as a hideout. At the bar, Skip, Ash's friend, introduces him to Shunichi Ibe and his assistant, Eiji Okumura, who are Japanese photographers reporting on American street gangs. However, their conversation is interrupted when Shorter Wong, one of Ash's allies, calls to warn him about Dino. Soon, Dino's men storm the bar, and in the ensuing chaos kidnap Skip and Eiji. Now, Ash must find a way to rescue them and continue his investigation into Banana Fish, but will his history with the mafia prevent him from succeeding? [Written by MAL Rewrite]

Otonashi awakens only to learn he is dead. A rifle-toting girl named Yuri explains that they are in the afterlife, and Otonashi realizes the only thing he can remember about himself is his name. Yuri tells him that she leads the Shinda Sekai Sensen (Afterlife Battlefront) and wages war against a girl named Tenshi. Unable to believe Yuri's claims that Tenshi is evil, Otonashi attempts to speak with her, but the encounter doesn't go as he intended. Otonashi decides to join the SSS and battle Tenshi, but he finds himself oddly drawn to her. While trying to regain his memories and understand Tenshi, he gradually unravels the mysteries of the afterlife. [Written by MAL Rewrite]