Stohess District raid

The Sutohesu-ku kyūshū (ストヘス区急襲) was a conflict between the Survey Corps and the Female Titan within Stohess District, the eastern city of Wall Sheena, in which the Female Titan was captured and the existence of Titans within the Wall was discovered.

Prelude
During the 57th Expedition Outside the Walls, Armin Arlert encountered Annie Leonhart, the Female Titan, and was able to deduce her identity after considering her actions during the expedition and seeing her Titan's face close-up. After the Survey Corps' return to Karanes District, he shared this deduction with Commander Erwin Smith, who devised a plan to capture Annie in Stohess District, Annie's base of operations in the Military Police Brigade and the half-way point between Karanes and Mitras where the Survey Corps had been summoned to hand Eren Yeager over to the MPs. This plan was shared with Eren, Mikasa, and Captain Levi first, though Eren was in great disbelief and denial at the possibility that Annie was the Female Titan.

While a majority of the Survey Corps made their way from Karanes to Stohess on their way to the capital, a squad headed by Mike Zacharias supervised a group of new Survey Corps recruits, leading them to an isolated base in Wall Rose where they would be under close watch. This was done to isolate Annie from any potential accomplices who could aid her during the Stohess District raid.

Annie Leonhart, having returned to Stohess District after her failure to capture Eren Yeager, began to oversleep in the days to come due to the great stress brought on by her prolonged time spent in multiple Titan forms.

First encounter
On the morning of the raid, the new recruits of the Military Police Brigade, including Annie Leonhart, were assigned with escorting the Survey Corps through Stohess District on their way to Mitras. As Annie joined her comrades on their way to the escort mission, she was beckoned aside by Armin who informed her of a plan by the Survey Corps to sneak Eren out of the district. After some convincing, Annie agreed to help Armin and the others. Suspecting a trap, Annie equipped herself with a blade-ring in order to trigger a Titan transformation if necessary.

With Eren and Mikasa, the four made their way to the entrance of a tunnel of an abandoned underground city which would lead them to the outer gate of Stohess. In reality, the tunnel was chosen to restrict Annie's ability to transform into a Titan and Survey Corps soldiers would await them below to capture her. Meanwhile, various members of the Survey Corps in civilian disguises waited out of sight in the event that the first plan failed. Annie hesitated to follow them underground, and the others questioned her choice with as little suspicion as possible. However, their conversation quickly became heated as Annie realized she was cornered, no longer denying her identity as a Titan. Mikasa became impatient and prepared to strike as Annie readied herself for Titan transformation, but Armin fired a signal flare to alert the disguised soldiers of the plan's failure. The soldiers quickly rushed Annie and restrained her, but Annie successfully slashed her thumb with her blade-ring and transformed, killing the soldiers around her as Eren, Mikasa, and Armin fled into the tunnel.

The three recruits attempted to meet up with the soldiers in the tunnel to initiate their plan B, but Annie's Female Titan stomped a hole into the tunnel, killing the team before any action could be taken. Eren proposed transforming into a Titan in order to shield himself and his friends from Annie, but his internal denial about Annie's betrayal prevented him from transforming. Armin proposed that he and Mikasa would split up and leave the tunnel from both the entrance and the hole left by Annie's foot at the same time, dividing her attention in order for Eren to safely escape. Eren wondered at his friends' ability to accept Annie's betrayal, and Mikasa simply attributed it to the cruelty of the world. Eren accepted this and found the strength to transform, engaging in battle once again with the Female Titan.

Anime and Manga Differences

 * In the manga, Mikasa's words to Eren about the cruelty of the world are enough to inspire him to fight Annie Leonhart. In the anime, Eren is trapped beneath the collapsing tunnel before he can make up his mind, and he is later lectured by both Jean and Armin in the midst of combat between the Survey Corps and the Female Titan before he gains the will to fight.
 * In the anime, Hange Zoë and her soldiers are seen using the special target restraining weapon to prevent the Female Titan from escaping after Eren is trapped in the tunnel. This backup plan is absent in the manga.