Fullmetal Alchemist Volume 18: 09/08/12
In Fullmetal Alchemist Volume 18 by Hiromu Arakawa the homunculi finally show their cards. Part of this is their own foolish pride but mostly it's due to the ticking of the clock. They are on a deadline and it is rapidly approaching.
Riza Hawkeye begins working for the Bradleys and she quickly realizes Selim's secret. Meanwhile in Fort Bragg, they figure out what the tunnels are for. Communications are then sent in the language of flowers.
All of this scrambling about gives characters a chance to develop, something that hasn't happened in the last couple of volumes. The relationship between Hawkeye and Mustang, as well as Mustang's background. It's the first real glimpse of what makes him tick.