The Other Side of the Gate

Envy delivers the captive Alphonse to Dante, sneering that the countless dead of Reole and Ishval reside within the Philosopher's Stone the boy has become. Following his father's old journal, Edward slips through a hidden passage beneath an abandoned church and uncovers an ancient city sealed underground four centuries ago to bury the truth of the human lives spent making a Stone, work he suspects Hohenheim had a hand in. As Izumi struggles against the cyborg Archer at Central Command, Ross and Brosh arrive with reinforcements to shield her.

Reaching Dante's lair, Edward finds Rose dancing in a daze. He unmasks Lyra as Dante, listing the slips that gave away her faked death, and grasps that the Stone lets her leap from one body to the next across centuries. Dante confirms that the buried city's people were sacrificed for a Stone that Hohenheim forged, and she frames her repeated genocide as a mission to keep humanity from destroying itself with the very power she hoards. She means to seize Rose's body using the Stone within Alphonse and refuses to say where the younger brother is.

When Gluttony bursts in mourning Lust, Edward turns him aside, then trades blows with Dante, whose transmuted stone serpent proves her rotting flesh cannot house her soul forever. Dante presses her real weapon, the claim that equivalent exchange is a lie, and her litany of unrewarded effort plants a seed of doubt in Edward. As she snatches Rose's baby with her serpent, a circle on the infant activates and hurls Edward through the Gate. He wakes in a stranger's body beside his father, who urges him to run, for zeppelins are raining bombs on London in the midst of the First World War.

Edward discovers the ancient city buried beneath Central and confirms that Dante, wearing Lyra's body, has steered the homunculi across four hundred years by transferring her soul. Dante reveals her genocidal mission to hoard the Philosopher's Stone and shakes Edward's belief in equivalent exchange. A transmutation circle placed on Rose's baby flings Edward across the Gate into a parallel world, where he awakens beside Hohenheim as zeppelins bomb wartime London.

The episode shares its Japanese title with the series' second ending theme, To the Other Side of the Door.