Stumbling in the darkness, Edward Elric finds himself in a sea of blood seeking to find anyone and anything to help explain where he has ended up. After a bit of wandering alone, he begins to blame Ling Yao for having gotten them in this mess in the first place, even calling him "Idiot Prince". The two of them meet up together and once they confirm that they aren't actually Envy in disguise, they start to realize that they've ended up inside of Gluttony because of the immediate debris on fire due to Roy's flame alchemy.
Trekking through the blood and continuing to examine the ruins left behind in Gluttony's stomach, Ed and Ling happen to find the detached metallic arm from Alphonse Elric's suit of armor. Ed confirms with Ling that Al didn't end up stranded with them inside of Gluttony, breathing a sigh of relief (and after a failed Elric Telepathic Communication), the two of them come across more and ruins as they search for the exit. They devise a plan to open a hole in the floor and drop the stick used as a torch to listen for a thud sound. With no indication of a thud, they frantically run to hurry and find the exit even more fearful of the unending nature of the terrain.
Meanwhile, May is trying to find a lost Xiao-Mei for which May explains has been with her since she was much younger. May likens their unusual companionship to the reality of her clan being the weakest and poorest of the 50 clans in Xing. Once she finishes her story of how they grew and lived together, as well as explaining that they are searching for the source of immortality to save their clan, Scar acknowledges that there is some time before the sun would come up and agrees to search for Xiao-Mei with May.
Back inside of Gluttony, Ed decides to do another test in which he uses the gun he got from Riza before they left to fight the homunculi. This new test was to see if they could hear the sound of the bullet hitting a wall from within Gluttony, but again the test is a failure as they don't hear anything as a result. Feeling defeated with hunger and exhaustion setting in, their optimism takes a crushing blow. Ling, now giving in to his hunger tells Ed to go on without him, however, an angry Ed, determined on returning to the others, decides to carry him along in protest reminding Ling that he has people waiting for him on the other side as well. They make their way to a circular stone and fall down in exhaustion, laying on the stone and contemplating the never-ending amount of space there seemed to be in this space. Thinking back to their issue of lacking any food to eat at the moment, Ed remembers that leather goods are edible as he takes off his boot. Once Ling confirms that the boot was the one used on Ed's automail leg, they decide to eat the boot and purify the blood to turn into drinking water.
After they come to their senses, Ling apologizes for having gotten them into this mess when Ed disagrees saying that "Compared to the training I did as a kid, this is nothing." But before they can mobilize once more, they are interrupted by Ling sensing a new presence in the darkness, Envy. Ed aggressively asks Envy to show him the way out and Ling detests noting Ed's willingness to give in to the enemy easily just for a way out, but Envy rebuttals that there is no way out, explaining that they are definitely inside of Gluttony but this place was better defined as a failed portal created by their Father. Ed now begins to fear that there is no true way out and that he'd be breaking his promise to Al on making his way out, in anger Ed furiously asks if King Bradley was the father of the homunculi. Envy confirms that he isn't their father, but does confirm that Bradley isn't a human.
The discussion topic having turned to Ishval, Envy happily expressed his joy for having been the one responsible for causing the Ishval Civil War by shooting that innocent child, disguised as an Amestrian officer. What was worse was that the officer was a humble soldier who had opposed military intervention in Ishval and in response to the shooting he was court-martialed by the military council. Ed now piecing together all the lives shattered by the war punched Envy in a fit of rage for destroying everyone's lives. Envy in response transforms into his true form, a grotesque monster filled with the lost souls of those who had been consumed by him.
With the fighting having started inside of Gluttony, Alphonse now with Xiao-Mei, realized they had been separated from the others. Agreeing on their confusion in what to do next, Gluttony mentions that father would be angry with him, leading Alphonse to realize that the Homunculi have a father. Once Alphonse fights his internal struggle of whether or not Ed is still alive, he quickly asks Gluttony to take him to their father.
- The scene in which Ed uses the pistol to test whether they could hear the sound of the bullet hitting a wall was omitted from the Fullmetal Alchemist: Brotherhood anime.