First Battle: The Struggle for Trost, Part 1

Atop the breached Wall, Eren registers that the Colossal Titan struck the mounted cannons deliberately, proof of intelligence behind the attack. He closes in with his ODM gear, weaving past a slow swipe, but a blast of searing steam stalls his approach and his killing stroke cuts empty air: the giant has vanished as abruptly as it appeared.

Trost mobilizes. Garrison veterans dread a repeat of the catastrophe five years earlier, civilians stream toward the inner gate, and Commander Pyxis abandons a chess game with Lord Wald, taking the nobleman's liquor with him as he heads for the front. Woermann divides the cadets into squads to screen the evacuation. Panic ripples through the ranks; Jean seethes that he was one day from a safe Military Police posting, and Eren counters that surviving training means they can survive this. Mikasa, pulled away to the rear guard against her wishes, asks only that Eren stay alive.

Eren's squad joins the middle guard eager to distinguish itself, but the Titans are already deep in the city. An abnormal springs on the unit mid-flight and swallows Thomas Wagner. Charging after the killer in a rage, Eren loses his leg to a second Titan's bite and crashes to a rooftop. His squadmates die around him one by one while Armin, frozen in shock, is lifted into a Titan's mouth. The sight drags Eren back to a Shiganshina memory of Armin's forbidden book about the outside world, the seas of flame and ice fields it promised. Refusing to die before seeing it, Eren hauls himself up, wrenches Armin free of the Titan's throat, and takes his place. Bracing the jaws with a blade, he vows again to reach the outside world before the mouth snaps shut, severing his arm and swallowing him. Far away, Mikasa turns, sensing something wrong.

Eren attacks the Colossal Titan and recognizes its intelligence from the targeted destruction of the gate and cannons, but the giant disappears before his blades connect.

The cadets are thrown into Trost's defense as their first battle; Pyxis leaves the interior for the front while civilians evacuate.

An abnormal Titan devours Thomas Wagner, and the counterattack collapses: a Titan bites off Eren's leg and his squad, including Mina Carolina, Nack, and Milieus, is annihilated.

A traumatized Armin is seized and placed in a Titan's mouth.

Eren, driven by the dream of the outside world from Armin's childhood book, throws Armin to safety and is eaten in his place, losing an arm as the jaws close. Mikasa senses that something has happened to him.

The episode adapts the manga chapter First Battle, opening The Struggle for Trost arc. Wit Studio and Production I.G produced it with Shinpei Ezaki directing and Hiroshi Seko writing; Feuerroter Pfeil und Bogen and Utsukushiki Zankoku na Sekai bookend the episode. Crunchyroll released it as First Battle - Battle of Trost (1).

Eren's last words inside the Titan's jaws, refusing to die before seeing the outside world Armin described, form the episode's signature quote and the emotional hinge of the arc.

A classroom flashback delivers the series' foundational Titan exposition: regeneration, no need to eat, unknown reproduction, and the nape as the sole fatal weak point. The lore segment covers wall-mounted artillery, humanity's pre-ODM anti-Titan weapon, contrasting movement-stopping grapeshot with powerful but wildly inaccurate shells.