The first episode alone justifies this entire OVA, Ilse's Journal gives you a Titan that talks, a moment that breaks everything you think you understand about them, and Hange's reaction that explains why she becomes obsessed with them for the rest of the series. The second and third episodes are thinner, mostly filler that exists to show you who the 104th were before everything fell apart. If you're already deep in Attack on Titan, this is essential for understanding Hange's character; if you're casual, the first episode is the only reason to care.

Three OVA episodes expand on the Attack on Titan story. In the first, the Survey Corps is on its 49th scouting mission when Hange Zoë, eager to capture a titan for study, rides off alone without Commander Erwin Smith's approval to confront one near a forest. The titan behaves strangely and leads Hange to the legacy of fallen scout Ilse Langnar, whose diary records her final moments and may prove vital to titan research. The second follows Jean Kirstein, who hopes for a comfortable life in the Military Police, as frustration with his fellow cadets pushes him to challenge Sasha Blouse to settle who is strongest. The third sends a squad of the 104th Training Corps, led by Marco Bott, on a dull forest ride that splits the group before trouble catches them unprepared.