Picking up immediately after the capture of the Female Titan, humanity finds no time to celebrate as a new threat emerges: Titans have been spotted within the supposedly intact Wall Rose. As the Survey Corps races to find the breach, they encounter the terrifying and highly intelligent "Beast Titan," a creature capable of commanding other Titans and speaking the human tongue. Amidst the chaos, the focus shifts to the 104th Training Corps members, specifically the enigmatic Ymir and Christa Lenz, whose hidden pasts hold the key to the walls' secrets. The situation escalates into a desperate struggle for survival when a massive betrayal from within the ranks forces Eren into a high-stakes battle that reveals a world-altering power hidden within him.