Attack on Titan: THE LAST ATTACK is the series' fifth compilation movie, retelling parts 3 and 4 of the fourth season of the Attack on Titan series based on the manga by Hajime Isayama.
Summary: In the past, a young Eren Jaeger sits dozing under a tree and hears a short-haired Mikasa Ackermann tell him that she will see him later. Moments later, he wakes as if from a dream and Mikasa tells him they should head home from their task of gathering firewood. He does not remember the dream, but Mikasa points out that he is crying.
Trivia: The anime series' director Yuichiro Hayashi has said that he storyboarded the THE FINAL CHAPTERS specials to be viewed together as a single film and that he considers this compilation film to be the optimal format to view the story. Ian Dietrich is erroneously depicted with a Scout Regiment logo on his jacket rather than the Garrison Regiment logo. The last part of Armin and Eren's conversation in the Paths features changes from the manga that were given to the anime staff by Hajime Isayama.
Source: Attack on Titan: THE LAST ATTACK, available under CC BY-SA 3.0.