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The Utopia District is briefly mentioned by Armin Arlert in the mission to rescue Eren Yeager from the Armored Titan. He tells Bertolt Hoover that Annie Leonhart has been captured and that she is currently being tortured for information in the district's underground. This distracts Bertolt long enough for Erwin Smith to climb on the Armored Titan and swing his sword down Bertolt's torso, freeing Eren who was tied to his back.