
The long-awaited shonen series Attack on Titan, written by Hajime Hisayama, is returning soon with a new season. here’s a recap of season 1
Premise

The anime series Attack on Titan is set in a world where humanity lives within walls to protect itself from Titans, man-eating giants that lurk beyond the walls. The walls are divided into three concentric layers, Wall Maria is the outermost Wall, Wall Rose is in the middle, and Wall Sina is in the center. with four outlying districts in each cardinal direction.

The society is ruled by a monarchy and system of lords, with a Church of the Walls that worships the walls. The military has three branches: the Garrison mans the walls, the Military Police handles internal affairs, and the Survey Corps launches expeditions beyond the walls.
Introduction

The introduction of the show follows the story of Eren Yeager, a young boy who dreams of joining the Survey Corps and experiencing freedom outside of the walls. His dreams are shattered when the titans destroy the gate of his hometown and kill his mother. Eren and his best friends Mikasa Ackerman and Armin Arlert become refugees and eventually join the military as part of the 104th Training Corps.
After three years of training, they graduate and are ready to join the fight against the Titans. Along the way, Eren forms a rivalry with fellow trainee Jean Kirstein, makes friends with Reiner Braun and Bertolt Hoover, and takes hand-to-hand fighting lessons from a girl named Annie Leonhart.
First Arc: the Siege of Trost

The first arc begins on the day of their graduation when Eren and some other trainees are cleaning Wall Rose, Suddenly, the Colossal Titan shows up and attacks the Trost District, the southernmost city of Wall Rose. Eren attempts to fight it, but the Colossal Titan seemingly disappears in a cloud of steam.
As the Titans continue to attack the city, Eren leads a squad of his fellow trainees, including Armin, but they are quickly attacked and wiped out. Eren saves Armin from being eaten by a Titan, but Eren is swallowed, losing his arm. Mikasa is assigned to the rear, helping with the evacuation and slaying Titans.

Meanwhile, Jean and several other trainees manage to reach the supply depot, despite heavy casualties. Armin, Mikasa, and Connie Springer, another recruit, successfully lure a Rogue Titan, who is attacking other titans for some reason, to the supply depot, and it begins to kill the ones swarming the building.
We discover that the Rogue Titan is in fact Eren in a Titan’s body. and when he is able to regain control, successfully uses the boulder to seal the breach in the wall, and the soldiers are saved by Captain Levi and his squad, the Survey Corps.
Eren is taken into custody and is allowed to join the Survey Corps under the supervision of Levi.
Second Arc: the Female Titan

Eren is placed in Levi’s Squad, which is made up of the Survey Corps’ most elite soldiers, and meets with commander Hange Zoe, a high-ranking Survey Corps officer who enjoys studying Titans. The Survey Corps conducts experiments on two captured Titans, named Sawney and Bean, but they are mysteriously killed by an unknown soldier.
The rest of the 104th Training Corps graduate and choose which military branch to join, with many of them joining the Survey Corps. Commander Erwin, head of the survey Corps plans to launch an expedition to reach Shiganshina District to find answers about Eren’s father, Grisha, and his Basement, which is said to contain information about the titans. On the expedition, a Female Titan appears that has intelligence. It can selectively harden its skin into crystal armor, making it extremely difficult to kill.

The Female Titan is ultimately revealed to be Annie, a fellow trainee, and Eren and the military attempt to capture her within the walls, but she encloses her human self within an unbreakable crystal. The crystal is taken into military custody.
Erwin is questioned by the government and military but is ultimately spared despite the amount of damage done and the lives lost. The battle also caused some minor damage to the Wall, and it is revealed that there is a massive Titan inside the Wall.
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