|Something stronger. Something larger. She gave birth to an undying body. And then she escaped to a world that was free... of even death.|
|— Zeke Yeager explains how Ymir became the first Titan and entered the Paths|
Zeke Yeager and Armin Arlert converse in the Paths about the nature of life and how in her fear, Ymir Fritz managed to escape to a world without death. Zeke does not believe escape is possible, and that it is pointless since to live also means to eventually die. However, Armin speaks about personal moments that are precious to him, even if they are not in the service of continuing their species, and Zeke realizes that he has moments like those that he cherishes as well. This leads to them meeting several previous Titan inheritors who had passed away before them and they chose to connect with those they are closest to before requesting their help.
In the outside world, some of the Titans change sides, with Bertolt Hoover, Ymir, and the Galliard brothers' Titans moving to protect Reiner Braun and Annie Leonhart. Mikasa Ackerman catches up with the Beast Titan that had eaten Armin, and with help from Gabi Braun, manages to cut him free. Jean Kirstein grabs the detonator and triggers the explosives to blow off the Founding Titan's head and Reiner tackles the centipede-like spine that emerges, trying to reconnect with it. Falco Grice picks up most of the team on his flying Jaw Titan save for Reiner and Armin, and clears the area so Armin is free to transform into the Colossus Titan and destroy the Founder's body.
As both Zeke Yeager and Armin Arlert reside within the Paths, the former begins to tell the latter a story about how life was able to form a long time ago due to the desire for it to multiply. However, it also dealt with the fear of death and extermination, eventually leading to the point where Ymir Fritz gave birth to an undying body and escaped to a world that was free of death. Armin asks what Ymir's ultimate goal is and Zeke admits he does not know even after spending so much time trying to understand her. He wonders why Ymir never defied King Fritz and remained obedient to his wishes for two thousand years. Eren Yeager was able to understand her attachment to the world she left behind when Zeke himself did not, leading to Ymir to go with him.
When Armin asks if there is still some way to get back to the outside world, Zeke thinks it is impossible. He asks Armin why he refuses to give up and if continuing his species is that important to him. What is happening now is the result of lifeforms controlled by fear. Armin protests that he and his friends are fighting fear, but Zeke is unmoved, because living means one day dying. He speculates that death might even bring relief from the days of being manipulated by the drive to multiply.
Armin glances down and notices a leaf in the sand. Picking it up, he tells Zeke of a childhood memory when Eren challenged him and Mikasa Ackerman to a race to a tree on a hill. While he had no chance of winning, Armin reflects on how running felt good to him and he wondered if he was born so he could be in that race. He has had other, similar memories of small, personal moments that he has come to regard as precious. However, to Zeke's surprise, Armin is not holding a leaf, but a baseball. When Armin says that his memories are precious even though they are unnecessary for a species to multiply, Zeke agrees, thinking back to his time playing catch with Tom Ksaver. He takes the baseball from Armin and looks at it fondly. He says that he would much rather have continued playing catch.
Meanwhile, Pieck Finger is injured outside of her Titan and Jean Kirstein saves her. Though she wishes to keep fighting, he says she is at her limit and plans to retreat towards Reiner Braun. However, the Armored Titan has been pinned down by the previous War Hammer Titans, with one armed with a sickle preparing to finish him off. Further towards the back, near Bertolt Hoover's Colossus Titan, Annie Leonhart is overwhelmed by several of the Titans. Suddenly, Bertolt's Colossus attacks the Titans swarming Annie, swatting them aside. Pieck, Jean, and Reiner witness Marcel, Porco, and Ymir's Jaw Titans biting and fighting off the Titans surrounding them.
Though Mikasa does not know what to make of Bertolt's Colossus, she decides not to waste the opportunity and chases after the okapi-shaped Beast Titan. From the back of Falco Grice's flying Jaw Titan, Gabi Braun fires a round into the okapi's head and manages to stun it, allowing Mikasa to free Armin by slashing the Titan's jaw open. Armin falls out and the Beast Titan's tongue shoots through his leg to grab him. He fires a Thunder Spear into its head, killing it, and Connie Springer cuts him free of the falling corpse. Annie is then able to catch Armin.
Behind Annie, the Survey Corps is shocked to see several of the Titans are fighting each other. Zeke partially emerges from one of the Founding Titan's spines and waves to Falco's Titan, calling out to Levi Ackerman. Armin explains that the current turn of events is thanks to Zeke, who woke up everyone who was sleeping in the Paths. He thinks that the reason all Eldians are connected through the Paths is because Ymir Fritz wants to be connected to them. She wants something.
In the Paths, Zeke told Ksaver that he did not think their plan was mistaken, but he would not mind being reborn if it meant he could play with him again. He also thanked his father, Grisha. Armin took the time to speak with Bertolt about how he took everything from him, so he knows that they cannot stay here. They asked the others to help them before leaving.
On the spine, Zeke takes a moment to appreciate how beautiful the day is and wishes he had noticed it earlier, but supposes that is too much to ask because of all the killing he has done. In the next moment, he is beheaded by Levi and the Rumbling stops, with the Wall Titans coming to a halt.
At Reiner's urging, Jean rushes for Eren's head and grabs the detonator that Pieck left behind. Calling Eren a suicidal blockhead once more, Jean detonates the explosives, blowing off the Founding Titan's head. Jean spots the centipede-like creature Gabi spoke of emerge from the neck, trying to reconnect to Eren's head. Reiner hurls himself at the expanding spine and wrestles it to the ground to keep it from the severed head.
Falco, now carrying nearly all of their group, picks up Jean and Pieck so Armin can blow up the Founding Titan's body with everyone else clear. Jean is worried about Reiner, but Pieck says that the Armored Titan can withstand the Colossus Titan's explosion. Reiner is prepared for the consequences and they should not waste this opportunity.
As Falco flies away, Armin thanks his friends and the Titan inheritors for their help. He then says good-bye to Eren before transforming.