Attack on Titan Season 3 Part 2 Episode 3, which is titled “Descent,” started with the flashback of Reiner Braun and Bertolt Hoover. While everyone was busy protecting Eren Yeager, Reiner and Bertolt were talking about the things that could happen if the Founding Titan succeeded to seal the hole they have finally opened for the Titans. When Reiner talked about his “Titan,” they started to realize that someone was listening to their conversation — Marco Bott, a member of the Survey Corps who graduated as the seventh highest ranked trainee in his class.
Reiner and Bertolt told Marco that all the things they said were just a joke. Marco made it look like he believed Reiner and Bertolt, but after moving to another location using the 3D Maneuver Gear, he came to a conclusion that the two could also be humans who could transform into Titans like Eren. Reiner and Bertolt knew how intelligent Marco is, so before he told other members of the Survey Corps about their true identity, they decided to make a tough decision.
Attack on Titan Season 3 Part 2 Episode 3 revealed how Marco died. After successfully capturing him, Reiner ordered Annie Leonhart to remove his 3D Maneuver Gear so that he couldn’t run away from the Titans. Annie hesitated at first, but Reiner told her that she needed to prove that she’s a real “warrior.” While seeing Marco being devoured by a Titan, Reiner, Bertolt, and Annie all felt a sense of guilt.
Attack on Titan Season 3 Part 2 Episode also featured the meeting of Reiner and Bertolt with War Chief Zeke Yeager. Reiner and Bertolt insisted that they should focus on freeing Annie, but Zeke told them they needed to stick to their mission to find the “Coordinate.” If Reiner won’t change his mind, Zeke expressed his desire to fight him again. However, when he lost for the second time, Reiner needed to surrender the power of the Armored Titan to another warrior.
The latest episode of Attack on Titan finally featured Bertolt showing up at Shiganshina District. It was revealed that Bertolt was hiding inside the luggage located at the back of the Cart Titan. Upon sensing that Reiner was in danger, the Beast Titan threw Bertolt inside the walls of Shiganshina District. Before Bertolt transformed into the Colossal Titan, Armin Arlert tried to negotiate terms of surrender.
However, Bertolt refused, saying that all of the members of the Survey Corps and the people inside the walls should die. The explosion of Bertolt’s transformation caught Hange Zoe’s squad. The Colossal Titan started to burn everything in front of him, making it harder for Eren and the Survey Corps to escape.