The fight against Envy proves to be difficult, and Ed has a hard time fighting something that has individual souls on it asking for his help. After getting slammed into the ground, he ends up getting swallowed by Envy. Inside of Envy, Ed regains consciousness near the Homunculus Philosopher's Stone, and seeing it allows him to make a sudden realization. He figures out a way to get out of this world, and he uses this fact to get Envy to release him. Back in the real world, May Chang has been looking for Shao May and manages to find the panda going underground with Al and Gluttony. She and Scar follow them down, but whereas Al and Gluttony are able to get through without incident, Scar and May Chang have to fight wave after wave of Chimera guards. What bothers May Chang is that she senses something bad underneath them, but it's not more Chimera, it's a person.
Meanwhile, Wrath tells Mustang of his past being raised in a facility with the other candidates to become Fuhrer. He was the one who survived the process of combining a Philosopher's Stone with a human body, so he became the country's leader. Mustang thinks that Wrath could still live as a human, but Wrath is prideful of being a Homunculus. Back in the world inside of Gluttony, Ed has Envy gather all the pieces of a stone mural. Ed realized that the pieces are all from Xerxes and match the one he saw when he was there, and what's drawn on it is a human transmutation circle. His idea is to transmute himself, thereby disassembling and reconstructing himself, and that would open the Gate and allow them to escape back to the real world. Before he does this though, he confronts Envy about what happened to the people of Xerxes because he's realized that they all disappeared to create a Philosopher's Stone.
Envy doesn't deny it, but he refuses to tell Ed who's behind it or what the plan is for Amestris until after they escape. He's also willing to offer up some the Xerxes souls attached to him as the toll for opening the Gate, and he correctly guesses that Ed sympathizes with them because he wants to believe Al, who is also only a soul, is human as well. Envy asserts that those souls can't return to being human, and Ed has no choice but to use them. He hears the thanks of one of the souls as the transmute goes through, and the next thing Ed realizes, he's in front of the Gate. There are actually two Gates though, and sitting in front of the other one is Al's body. Ed immediately tries to run towards it, but the Gate he was in front of pulls him in, and Al explains that he can't come along because Ed isn't Al's soul. The Gates close once Ed has been pulled in, but a moment later, he punches his way back out to swear to Al that he'll one day come to get him.