In Fujisawa, Sakuta Azusagawa is in his second year of high school. Blissful days with his girlfriend and upperclassman, Mai Sakurajima, are interrupted by the appearance of his first crush, Shoko Makinohara.

When man-eating Titans first appeared 100 years ago, humans found safety behind massive walls that stopped the giants in their tracks. But the safety they have had for so long is threatened when a colossal Titan smashes through the barriers, causing a flood of the giants into what had been the humans' safe zone.

As the Trost District is reclaimed from the Titans, Eren is taken under the wing of Captain Levi and his squad, who decide to try and teach him to master his mysterious abilities.

Living by the sea, protecting the sea, and journeying across the sea…They’re the BLUE MERMAIDS! Because of a shift in tectonic plates around 100 years ago, Japan lost much of its area to submergence. To preserve Japan’s territories, Coastal Cities sprung up, one after the other. Eventually, they became Marine Cities, and along with the expansion of sea-lanes to connect them, the need arose for a sizable staff to protect the seas. At the same time, maritime jobs were becoming more popular among women. Hence, the BLUE MERMAIDS had become every female student’s dream job.

In the fourth recap movie, episodes 1 to 59 of the anime are retold, compiling the first Three seasons of Attack on Titan into a two-hour event.

After a draining December, Sakuta is quickly nearing the end of his second year of high school. Since Mai is a third-year student, they don't have much time left together before graduation rolls around. Meanwhile, his sister, Kaede, is slowly but steadily venturing outdoors again. Just as she begins to find her footing, she announces her most ambitious goal yet—attending her brother's high school! Sakuta knows better than anyone how difficult this will be for Kaede, and he's ready to support her however he can. He's just not sure if that's what's best for her...or what she really wants...