Attack on Titan is a Japanese manga and anime series that features a post-apocalyptic world where humanity is threatened by Titans, gigantic humanoid creatures who devour humans without reason. The story follows Eren Yeager, Mikasa Ackerman, and Armin Arlert as they join the Survey Corps to fight the Titans and unravel the mystery of their existence. Attack on Titan is known for its intense action, complex characters, and themes of humanity, survival, and sacrifice.