After being cornered by Izumi Curtis on the issue of their current armor-and-automail look, Ed and Al start to tell their story with this issue, finally revealing their "origin story" to the reader nearly two years after the original run of the Fullmetal Alchemist manga began. Why might Hiromu Arakawa have decided to hold back this information, rather than begin the story with it? Tim and Patrick discuss several good reasons for doing so in discussing chapter 21!