Several hundred years ago, humans were nearly exterminated by the Titans. Titans are typically several stories tall, seem to have no intelligence, devour human beings and, worst of all, seem to do it for the pleasure rather than as a food source. A small percentage of humanity survived by building a city protected by extremely high walls, even taller than the largest of Titans. Flash forward to the present and the city has not seen a Titan in over a hundred years, until one day, a Colossal Titan appears out of thin air and destroys part of the city wall. As teenage boy Eren Jaeger and his foster sister Mikasa Ackerman witness the destruction of their town and death of their mother at the hands of the Titans, Eren vows to kill every single Titan and take revenge for all of mankind.
Coupled with the military's cover-up of a previous incident, the shocking discovery inside the Walls causes a stir. Elsewhere, while the new Scout recruits are held for observation, a surprising threat appears.
With the appearance of Titans within Wall Rose, Sasha and Connie ride as messengers to warn their villages of the impending threat.
Scouts search for a hole in the wall while Eren and others learn that someone close knows all the answers.
Unarmed and overwhelmed by the Titan assault on the castle, the only hope for the Scouts may lie in a promise and a secret.
Utgard Castle comes crumbling down as Ymir desperately battles the Titans. Now, Christa must fulfill the promise they made long ago during winter training.
Following the battle, the Scouts regroup atop the wall only to find more questions than answers.
With a new enemy revealed, Eren and the Scouts fight back using all the techniques at their disposal.
Without a way to pursue the Titans, the Scouts have no choice but to recuperate as they wait for reinforcements. But do they still have faith in Eren?
The Scouts rally and charge in pursuit, but Reiner is not quite himself while the group is trapped in the giant forest until nightfall.
When their group finally flees, Ymir wonders whether she should lie or stay true to herself, even if it means ruining the lives and future of those she cares about.
The pursuit begins as the Recon Corps battles their way to Eren. But as the Scouts start to take numerous casualties, Erwin executes a risky strategy.
The battle continues as Eren and the Scouts face many hard decisions. Who is the real enemy? What is the war really about? And what will the future hold for mankind?