The 520 Cens Promise

When Envy finds Marcoh's dummy corpses and the word Vengeance on the wall, he realizes Scar has learned of Marcoh's part in the Ishval war. Ed leaves Hawkeye's home with her promise to reach him if anything arises and a message for Mustang that Scar is still active. Meeting Al, Ed shares what he heard and reflects that Scar and May kept their alchemy when Father shut everyone else's down, so hope remains for their mission. The next morning Ed learns from Dr. Knox that May has slipped away without a word, leaving Shao May as his only lead.

Mustang's subordinates disperse to distant postings: Breda gives Havoc dumbbells before West City, Fuery feeds Black Hayate before South City, and Falman returns a borrowed chessboard ahead of North City. Hawkeye collects her things from Mustang's office and passes on Ed's warning about Scar, urging him to stay alive. Alone, Mustang studies his chess pieces and notes his checkmate is not yet lost. After a day of asking Central's people about May, the brothers are offered a ride by Mustang, who agrees to inquire about her alkahestry link to Xing.

Reminded of the 520 cens Ed once borrowed, Ed decides to keep the debt until Mustang becomes Fuhrer, his way of insisting the man live long, and mentions that Hawkeye told him all about Ishval. Back at their hotel, the brothers find Ling's other bodyguard Fu, newly returned from delivering Maria Ross to Xing. Mustang passes Madame Christmas a sheet of paper, and she contacts Lt. General Grumman. At Knox's house, Fu is briefed, strikes and lectures Lan Fan for losing her arm, and finally weeps over his injured granddaughter.

Fu declines Ed's offer to take Lan Fan to Rockbell Automail, choosing an unknown mechanic since the enemy has seen her face, and bows in thanks to Knox before leaving in borrowed clothes. He warns Lan Fan that the failing Xing Emperor leaves them little time. Knox's estranged wife and son then arrive, his son wanting to become a doctor despite knowing his father's Ishval past, and Knox tearfully welcomes them. At Central Prison, Kimblee is released after hiding a Philosopher's Stone in his stomach; Envy, his driver, orders him to kill Scar and recapture Marcoh, hands him a fresh Stone made from Marcoh's researchers, and lets him destroy a town of his choosing. Scar, meanwhile, keeps Marcoh alive to translate his brother's notes and disfigures the doctor's face before heading North.

The title card array is the moon array tattooed on Kimblee's left hand. The 2009 series trims the conversation between Fu and the Elrics at Knox's house, dropping direct references to Winry and Pinako and cutting the scene of Fu changing clothes.

A small continuity error appears when Mustang places the white queen on e1 instead of the correct d1.