Ilse's Notebook: Notes from a Scout Regiment Member

Ilse's Notebook is the first OVA episode of the Attack on Titan anime. It is produced by Wit Studio and Production I.G, and it is included with a limited edition of Volume 12.

Overview
In year 850, the Survey Corps soldiers head outside the Walls for the 49th time. Hange, however, isn't satisfied with their plans this time and argues with Erwin about how important it is to capture a Titan for research purposes. In spite of Erwin's orders, she eventually heads into a forest to follow a Titan that exhibited strange behavior. The capture attempt, however, fails and the Titan is killed by Levi.

Near the same location, they soon find a corpse of a soldier, along with the soldier's notebook. After reading it, Hange learns that the soldier, Ilse Langnar, encountered a Titan who spoke to her. However, after an enraged Ilse continues questioning the Titan, it kills her, but surprisingly, doesn't eat her body. Later, Hange writes a document of proposal to Erwin for the resuming of the Titan capturing operations. Eventually, Hange gets an approval, much to her joy.

Summary
Sometime in year 850, the Survey Corps forces are readying themselves to go outside the Walls once again. An annoyed Hange tries to speak to Levi, but before she can even say something, Levi rejects the thought, knowing that Hange wants him to assist her with capture of a Titan. After Mike also refuses, the gate opens and the soldiers head out, starting the 49th expedition, much to Hange's enthusiasm. Later, while the soldiers are taking a break, Hange argues with Erwin, who refuses to approve of the Titan capture operation, as setting up a base is their priority. Hange then leaves the tent and angrily confronts Oluo, using Levi as an example of how knowing your opponent is important to defeat them.

On the look out, Mike notices a Titan in the nearby forest. While all other soldiers are to be on guard, Hange rides a horse to the Titan's direction, with Levi being ordered by Erwin to follow him. Eventually, she reaches the Titan and while attempting to talk to it, the chase begins. She leads it out of the forest, however, the Titan suddenly stops chasing Hange and heads back to the forest. Hange goes after it, with Levi and his squad following them. Eventually, the Titan reaches a certain tree and begins bumping its head into it. Hange, wondering what is going on, tries to approach the Titan, however, it attacks her, with the Squad Leader barely dodging. Suddenly, Oluo appears attaching the hook of his 3D Maneuver Gear onto the Titan's neck in an attempt to kill it, but Hange yells at him to wait. The moment of hesitation cause Oluo to be caught by the Titan, however, Levi frees him by cutting off the Titan's arm and killing it afterwards. He then confronts Hange for endangering other soldiers. At that moment, Petra notices a corpse inside the tree that the Titan approached. After learning that the soldier is Ilse Langnar, Levi finds a notebook lying nearby.

At unknown time during the Survey Corps' expedition outside the walls, Ilse is seen running through an unknown land, noting down everything that is happening around her. Her squad has been killed by Titans and her gear is broken, but in spite of that, she continues advancing in hopes of reaching home without encountering Titans. However, while running throug a forest, noting down the events, she suddenly encounters a Titan. She continues writing as the Titan isn't attacking. Thinking it's over, she writes down her last regrets, but suddenly, the Titan speaks a few words. Much to Ilse's shock, it bows down, while saying "Ymir-sama, welcome back", which Ilse writes down. She then tries to ask questions, without getting any response. Enraged, Ilse yells at the Titan for its species eating humans without any reasons, which causes the Titan to tear the skin off its face, much to Ilse's horror, who tries to escape, but to no avails, as the Titan catches her and crushes her head.

Hange, as she finishes reading the notebook, then begins writing a document of proposal to Erwin for the resuming of the Titan capturing operations within the Survey Corps. Using the diary as a base of her arguments, Hange wants to continue what Ilse has started. She then visits Ilse's family, showing them the notebook. Some time later, Hange is approached by Oluo, who wants to apologize, however, Hange is the one to do so. Her, Oluo, Levi and Petra then walk through the town, with Hange expressing her joy for being given a permission by Erwin to continue her research.