Sin

In the Underground Chapel, Historia Reiss tries to convince the chained Eren Jaeger that her father has been humanity's ally all along. Rod Reiss goes further. When father and daughter press their palms against Eren's back, memories flood him: this cavern, a burning chapel, and his own childhood self transforming and eating his father, Grisha Jaeger. Historia's touch unlocks memories of her own. A dark-haired young woman once visited her at the farm, taught her to read, urged her toward kindness, and wiped her memory after every meeting. Rod identifies the visitor as Frieda, Historia's elder half-sister, and reveals her fate: five years ago Grisha, already carrying the Power of the Titans, came to the cavern, devoured Frieda to take the Founding Titan she carried, and slaughtered Rod's wife and five children. Rod alone escaped. Kenny Ackermann interrupts with news that a coup has toppled the government, then heads up with his squad to hold the entrance.

In Mitras, Dhalis Zachary amuses himself torturing the noble Aurille, who spits back that his "slave blood" differs from the nobility's and his memories will soon be rewritten anyway. The interrogations all point the same way: the Reiss family can alter human memory, and only certain bloodlines resist it. Dot Pyxis warns Erwin Smith that if Rod obtains Eren's Scream, the coup itself could be erased from every mind in the Walls. Erwin marshals the Scouts and rides for Reiss territory.

On the road, Levi briefs his squad to treat Kenny as his equal or worse, given the man's specialized gear. He asks Mikasa Ackermann about her family, and she recalls the surge of impossible strength that woke in her the day of her kidnapping; Levi confirms both he and Kenny have felt the same awakening. A flashback shows a young Kenny learning from his dying grandfather why the Ackermanns were hunted: they and the Oriental clan resisted the King's memory manipulation and turned their backs on him. Above the cavern, Squad Levi finds the trapdoor in the rebuilt chapel while Traute Carven rallies the Anti-Personnel Control Squad below, reminding them of the meaning Kenny gave their lives.

Physical contact with Rod and Historia restores Eren's suppressed memory of eating his father as a child.

Historia recovers her erased childhood memories of Frieda Reiss, the half-sister who secretly raised and protected her.

Rod recounts how Grisha Jaeger stole the Founding Titan by devouring Frieda and wiped out the Reiss family.

The military learns the Reiss bloodline can rewrite memories and that the coup will be forgotten if Rod claims the Scream.

Levi reveals the Ackermann awakening phenomenon, which he, Kenny, and Mikasa have each experienced.

Squad Levi locates the hidden entrance beneath the chapel as Kenny's squad prepares its defense.

Sin is the sixth episode of the third season and the 43rd overall, a Wit Studio and Production I.G production. It compresses five chapters: Location of the Counterattack, Sin, Chains, Welcome Party, and Dreams and Curses. Ryuta Kawahara directed; Hiroshi Seko wrote the script.

The Japanese airing was August 27, 2018, the US airing September 30, 2018, with "Red Swan" and "Requiem der Morgenröte" as its themes.

Alongside Trust and Friends, this is one of only three episodes rated TV-MA for the Toonami/Adult Swim broadcast; the rest of the series ran at TV-14. The information segment covers the Scream, the command power shared by the Female Titan and, in stronger form, the royal family's Founding Titan.