Fullmetal Alchemist: Brotherhood - episode 35 - 05 Dec, 2009

Olivier and her crew manage to subdue Sloth by dousing him in fuel and sending him outside to freeze. Olivier then has the Elric brothers arrested so she can learn more about the homunculus. Kimblee, who is in the hospital, is visited by Lieutenant General Raven, who brings along another state alchemist who uses the philosopher's stone to heal his wounds. Meanwhile, Marcoh continues to look into alkahestry, with May teaching him about how it works. Edward, Alphonse, Olivier, Buccaneer, and Falman investigate the tunnel that Sloth made, where Olivier has Edward tell her everything. Edward and Falman deduce that the tunnel is being used as a giant transmutation circle for the philosopher's stone, and that Amestris itself was formed for that very purpose. Olivier talks with Raven while the others listen in on the conversation, and gets him to spill about immortal armies. (Source: Wikipedia)