The series follows the story of Eren Yeager, his adopted sister Mikasa Ackerman, and their friend Armin Arlert. After the outermost Wall is breached by Titans, including the 60-meter tall skinless Colossus Titan and the abnormally intelligent Armored Titan, and his mother dying in the resulting destruction, Eren vows revenge against the Titans and later enlists in the military, accompanied by Mikasa and Armin. Years later during his first battle against the Titans, Eren discovers that he has the ability to transform into a Titan at will. Seen as a threat to mankind by some, and as a ray of hope by others, Eren joins his companions in a desperate fight to protect what remains of their society while looking for answers to the mysteries surrounding the Titans, the Walls, and his own existence as well.

Hajime Isayama first wrote a 65-page one-shot version of Attack on Titan back in 2006.^[1] Before serialization, he had already thought of ideas for twists although they are fleshed out when he is working on them. While working at an internet cafe, Isayama encountered a customer who grabbed him by the collar. It was this incident that showed him "the fear of meeting a person one can not communicate with," which is the feeling that he conveys through the Titans.^[2] When designing their appearances, he uses several models such as martial artist Yushin Okami for the protagonist Eren Yeager's Titan form^[3] as well as Brock Lesnar for the Armored Titan.^[4] The "Wall of Fear" is reportedly said to have been influenced by Japanese culture as due to their people becoming very isolated and enclosed. The people's inner feelings is one of the series' main influences.^[5] The author estimated his basic monthly timeline as one week to storyboard and two weeks to actually draw the chapter. Isayama said he has the story planned out fairly far in advance, even marking down in which collected volumes a specific "truth" will be revealed.^[3] In September 2013, he stated that he is aiming to end the series in 20 collected volumes.^[6]

The manga series began its serialization in Kodansha's monthly publication Bessatsu Shōnen Magazine in its September 2009 issue. The firsttankōbon volume was released on March 17, 2010, with 11 volumes released as of August 9, 2013.^[7] In June 2013, the manga reached the mark of 20 million copies in Japan.^[8]

A comedic spin-off of the series, titled Attack on Titan: Junior High (進撃！巨人中学校 Shingeki! Kyojin Chūgakkō^?) and written by Saki Nakagawa, began serialization in Bessatsu Shōnen Magazine's May 2012 issue. It follows the main characters as they battle the Titans while in junior high school.^[9] Another manga series based on the prequel light novel Attack on Titan: Before the Fall started running in Kodansha's Monthly Shōnen Sirius from August 2013, drawn by Satoshi Shiki.^[10] An additional spin-off based on the A Choice With No Regrets visual novel began serialization inAria, titled Attack on Titan Gaiden: Kuinaki Sentaku (進撃の巨人 悔いなき選択^?) it is written by Gan Sunaaku and illustrated by Hikaru Suruga. It focuses on the origins of Levi, one of the most prominent characters in the main series.^[11]

In North America, the series is published in English by Kodansha Comics USA. They published the first volume on June 19, 2012,^[12] with 8 volumes released as of October 29, 2013.^[13] In October 2013, the manga reached the mark of 500,000 copies in North America.^[14] All three spin-off manga have also been licensed by Kodansha Comics USA, who will publish the first volume of each in spring 2014 and summer 2014.^[15][16]

A light novel series titled Attack on Titan: Before the Fall (進撃の巨人 Before the fall^?), written by Ryō Suzukaze and illustrated by Thores Shibamoto, began on December 2, 2011. Its story is set before the events of the manga and it is published by Kodansha. Three volumes have been published so far; the first tells the story of Angel, who invents the Vertical Maneuvering Equipment; and the following two follow a young man who was found as a baby in the stomach of a Titan. Vertical will release the novels in North America from summer 2014.^[17][18]

An anime television series adaptation produced by Wit Studio (a subsidiary of IG Port) aired on MBS between April 6, 2013 and September 28, 2013, directed by Tetsurō Araki.^{[19][20][21][22]} Both Funimation and Crunchyroll simulcast the series on their respective websites, and Funimation intends to release the series on North American home video in 2014.^[23][24] The anime has been licensed in the UK and Australasia by Manga Entertainment. An OVA version of the "Ilse's Notebook" special chapter from tankōbon volume 5 was originally scheduled to be released on August 9, 2013, bundled with the volume 11 limited edition. It has since been postponed to be included with a limited edition of volume 12 instead.^[25]

For the first thirteen episodes, the opening theme is "Feuerroter Pfeil und Bogen" (紅蓮の弓矢 Guren no Yumiya^?, lit. "Crimson Bow and Arrow") byLinked Horizon whilst the ending theme is "Utsukushiki Zankoku na Sekai" (美しき残酷な世界^?, lit. "This Beautiful Cruel World") by Yōko Hikasa. For episodes 14-25, the opening theme is "Die Flügel der Freiheit" (自由の翼 Jiyū no Tsubasa^?, lit. "Wings of Freedom") by Linked Horizon whilst the ending theme is "great escape" by Cinema Staff. Both "Feuerroter Pfeil und Bogen" and "Die Flügel der Freiheit" were released as part of the single "Jiyū e no Shingeki" on July 10, 2013.^[26][27]

Four video game adaptations of Attack on Titan developed by Nitroplus staffers in collaboration with Production I.G were announced.^[28] Nitroplus clarified that the studio as a company is not involved in the Attack on Titan Blu-ray Disc games, while individual staffers are.^[29] The games are visual novels and will be included in the first copies of the third and sixth Blu-ray Disc volumes of the anime. The games will cover spin-off stories about the characters of Attack on Titan. Hajime Isayama himself is supervising the development of the games; Production I.G is collaborating at the project too.

The third Blu-ray volume was released on September 18 with Seko's Lost In The Cruel World visual novel about Mikasa, and a preview of Gan Saaku'sA Choice With No Regrets (悔いなき選択 Kuinaki Sentaku^?).^[30] The sixth Blu-ray volume will be released on December 18 with the full version of A Choice With No Regrets about Levi and Erwin's past, Jin Haganeya's currently untitled visual novel about Eren and Levi, and Seko's Wall Sina, Goodbye visual novel about Annie.^[30]

An action game, titled Attack on Titan: The Last Wings of Mankind (進撃の巨人 ～反撃の翼～ Shingeki no Kyojin ~Hangeki no Tsubasa~^?, subtitle lit. "Wings of Counterattack"), is in development by Spike Chunsoft for the Nintendo 3DS for release on December 5, 2013.^[31][32][33]

A live-action film is in production. In December 2012, it was reported that Tetsuya Nakashima has left his position as director of the live-action film. According to film distributor Toho, Nakashima had considerable creative differences on the scriptwriting and other matters.^[34][35][36]

Attack on Titan won the Kodansha Manga Award in the shōnen category in 2011,^[37][38] and was nominated for both the 4th annual Manga Taishōaward and the 16th annual Tezuka Osamu Cultural Prize.^[39][40] The 2012 edition of Kono Manga ga Sugoi!, which surveys people in the manga and publishing industry, named Attack on Titan the 8th best manga series for male readers.^[41] Six of the seven English volumes published in North America charted on The New York Times Manga Best Seller list for the week of October 13, 2013, and volume one has been on the list for 20 weeks.^[42][43] Volume one was also number one on Nielsen BookScan's list of top 20 graphic novels in American bookstores for October 2013,^[44] and for the month of September, the series had more volumes on the list than another other series.^[45] The Young Adult Library Services Association in the United States named the series one of its "Great Graphic Novels for Teens".^[46] As of June 2013, the series has sold over 20 million copies in Japan. The anime is noted to have helped in boosting the series' sales while Mainichi Shimbun called it a "once-in-a-decade hit."^[47]

Many have analyzed Attack on Titan as representing "the hopelessness felt by young people it today's society."^[48] While writer Mao Yamawaki called it a "coming-of-age story of the boys and girls at its core", with a new mystery every episode. It is these mysteries that critic Tomofusa Kure says amplifies readers' expectations. The artwork of the manga has been criticized as crude by some reviewers, with Isayama himself admitting his drawings are "amateurish." However, those same critics stated that after years of serialization, the art has been improving, and Kure believes that had the illustrations been "refined", it would not have conveyed the "eeriness" that is a key characteristic of the work.^[48]

The anime has won multiple prizes during the 3rd Newtype Anime Awards, including best director, best script, best soundtrack, runner-up for commercial, best theme song, top female character, and title of the year.

.^[49] Carl Kimlinger from Anime News Network was sharply critical of the first two episodes of the anime adaptation. He did praise the show for "[bringing] back the terror of the fee-fi-fo-fum set", but then said that it "does not a good show make". Kimlinger criticized Araki's direction, saying he "clearly intends it to be powerful and unsettling, but it's just crude and unpleasant."^[50] On the other hand, other critics from Anime News Network praised much of the series. Rebecca Silverman said it "is both gorgeous and appalling in its visuals", and "an excellent mix of what 18th century Gothic novelist Ann Radcliffe defined as horror versus terror: the one is physical, making you want to look away, and the other is intellectual, making you want to know what's going to happen next. "^[51] Though there are several apocalyptic action shows, Carlo Santos noted that "few get as close to perfection as Attack on Titan does". Santos described it as "a masterpiece of death and destruction" even if he only watched the first episode.^[52] Theron Martin praised the musical score and the "intense, impactful first episode" despite he felt it has "limited animation". Martin also compared Attack on Titan's vibe and visual aesthetic to Claymore.^[53]