Eren Yeager, once an ally but now a foe, initiates a risky scheme guided by the enigmatic Beast Titan, Zeke. Obscuring his true motives, Eren seeks to end the age-old strife between Marley and Eldia by unorthodox means, delving into his family's enigmatic history. As Marley and Eldia clash using both human soldiers and Titans in a savage bid for supremacy, Reiner Braun deploys his own abilities to thwart Eren's militaristic endeavors. Amidst the turmoil, young Eldians Falco Grice and Gabi Braun struggle for survival. Simultaneously, Eren's childhood comrades Mikasa Ackerman and Armin Arlert, imprisoned alongside their former Survey Corps allies, witness Eren's unsettling metamorphosis. Holding onto hope that Eren's core goodness remains intact, Mikasa and the group join forces to rescue his humanity from the abyss.