That Day

Young Grisha and his sister Fay slip past Liberio's gate to watch an airship land. Two Marley Public Security officers catch them without permits; Grisha takes a beating from one, Kruger, while the other, Gross, offers to walk Fay home. Her corpse surfaces in the river the next day. Watching his father thank the lying officer and recite Marley's version of Eldian history, Grisha learns that survival inside the walls of the internment zone means swallowing every humiliation. The lesson curdles into hatred.

Grown and running his father's clinic, Grisha is recruited through a scarred patient into the Eldian Restorationists, where documents from an unseen informant called the Owl describe Ymir Fritz as a cultivator rather than a conqueror. The royal descendant Dina Fritz joins the cell, marries Grisha, and bears Zeke, whom the couple groom as their infiltrator once Marley begins recruiting Warrior candidates to seize the Founding Titan beneath Paradis. Grisha later recognizes he treated his son as a vessel for Eldia's hopes rather than a child. Zeke turns his parents in. Tortured and shipped to Paradis, the Restorationists are injected on the wall's edge and dropped, transforming into Pure Titans that chase the weeping Grice across the field below. Dina promises to find Grisha whatever form she takes; the Titan she becomes is the smiling one that will one day devour Carla.

In the present, Eren wakes screaming in a cell, having lived his father's memories, and realizes what his mother's killer once was. Back in the past, Gross confesses to feeding Fay to his sons' dogs and prepares to shove Grisha off the wall for sport, but Kruger throws the sergeant major to the Titan below instead. Declaring himself the Owl, Kruger slices his hand open and transforms.

Fay Jaeger is murdered after she and Grisha sneak out to see an airship; Gross later admits he let his dogs kill her.

Grisha joins the Restorationists, marries Dina Fritz, and learns the Founding Titan sits inside the Walls of Paradis.

Zeke betrays his parents to Marley Public Security, dooming the movement.

Dina becomes the smiling Titan, the same creature that eats Carla Jaeger years later, a truth Eren absorbs through his father's memories.

Kruger unmasks himself as the Owl, killing Gross and transforming into a Titan before Grisha's eyes.

That Day is the 20th episode of season 3 and the 57th overall, directed by Yōko Kanamori and written by Hiroshi Seko for Wit Studio and Production I.G. It aired June 17, 2019 in Japan and July 13, 2019 in the US, adapting the chapters That Day and Borderline. The episode runs without an opening theme.

Its English title repeats that of the series' second episode. During the scene where Grisha tells young Zeke he will become a Warrior, the boy plays with an ape toy beside a horse and two toppled soldier figures, quiet foreshadowing of the Beast Titan and the massacre of the Scout charge at Shiganshina.