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Alteration (改竄 Kaizan?) is the 4th episode of Toaru Kagaku no Railgun T. It was broadcast on January 31st 2020. The episode was directed by Sokuza Makoto and the screenplay written by Yasukawa Shogo. There is no credit for the storyboard of this episode due to reasons unknown.

Shrugging aside being scolded by Kuroko, Saten continues investigating on the urban legend of Shadow Metal. Uiharu finds a lot of strange reports filled with unreliable information, while Saten felt uneasy about the site that she saw but could not be found. As Uiharu becomes worried, Saten headed to the Kirigaoka grounds upon sensing a "conspiracy". Behind her, figures dressed in protective clothing emerged.

During this moment of trouble, all of the events of the day ended, and the morning after the well-received Daihaseisai's Night Parade came. Mikoto was asked by Wannai about her tracksuit. Unable to stop the feeling that something happened to her sister, Mikoto went on a pursuit to locate her whereabouts.


Kuroko laments to Mikoto that they would have to part ways again due to the tradition in Tokiwadai involving the students staying at a hotel with their parents during the Daihaseisai. Then, Mikoto is reminded of her clone upon seeing some students buy at the nearby food stalls and decides to treat Kuroko and the others for lunch. Saten, on the other hand, continues her search of any traces of the elusive Shadow Metal, with Uiharu doing her own search through the Internet. As Uiharu finds the high amount of search results unusual, Saten prepares to scour a Daihaseisai event venue field by hand.

Saten finds nothing resembling metal from the event venue. Meanwhile, Uiharu discovers that the site found by Saten earlier can no longer be found. Saten speculates a coverup performed by those who want to hide the truth about the Shadow Metal, and as Kuroko overhears their conversation, Uiharu warns Saten that anyone who would do the coverup may also see Saten as a threat. At that moment, several figures wearing protective gear approach Saten, putting their call to a stop. Kuroko immediately brings Mikoto with her to the Kirigaoka Girls' Academy grounds at School District 18 to rescue Saten.

Moments after Mikoto prematurely attacked those surrounding Saten, the "men in protective gear" revealed themselves as part of the cleaning crew assigned to prevent esper DNA from being extracted from the venue after an event. Saten and Mikoto apologize for the misunderstanding, and Kuroko explained that the urban legend of Shadow Metal was a rumor based on the increased security after a sporting event. Kuroko then proceeds to deliver a long lecture to the two troublemakers. Back at Judgment 177 Branch Office, Uiharu is relieved about how the incident was wrapped up, but her own curiosity soon brings her to spend more time lurking around. Using the large amount of dummy data she found, she manages to recreate the site that Saten found and later disappeared, called Auribus Oculi Fideliores Sunt, and proceeded to read into its contents, not knowing that someone is aware of the breach she just performed.

Mikoto, Kuroko and Saten soon return to the Branch Office. With Mikoto and Kuroko stopping Saten from bringing up Shadow Metal again, Uiharu decides to change the topic to a "secret spot for viewing fireworks" that she discovered earlier. The four then decide to go to this secret spot to enjoy the Night Parade event taking place every day during the Daihaseisai.

The next morning, Mikoto discovers that Misaki has not been seen since the night before. Mikoto also finds out that Wannai Kinuho has not yet received her gym clothes. Worried that something happened to her "sister", Mikoto follows her traces through footage of camera scattered across the city. Eventually, she finds a lead, with her clone unconscious and taken to an ambulance. Mikoto manages to talk to the EMTs on the scene, who claimed that they took the clone to a certain hospital, but she later discovers that no such thing had happened. Sensing discrepancies in the story of the EMTs, she extracts data from the ambulance's navigation system, which reveals that the ambulance passed by a large parking garage before returning. Soon, Mikoto loses her temper and, as soon as her cover was blown, both sides start accusing each other of tampering information. At that moment, Mikoto realizes that someone may have tampered with the memories of the ones she has just confronted.

Elsewhere, Kuroko endures another day without Mikoto's presence with Saten and Uiharu, and she notices that Uiharu has gone outside of their intended patrol route. Then, a man introduces himself as an "outsider" who has just been robbed. As Uiharu and Kuroko turn to respond to the apparent incident, someone with golden hair emerges from behind them to render them immobile.

The commotion near a certain hospital was eventually cleared out, with Watanabe apologizing in Mikoto's behalf and bringing her back after her incessant questioning about what happened to her clone. Watanabe then proceeds to remind Mikoto about her role as a Level 5 in the Daihaseisai and asks her to be careful about her actions. Although unable to persuade Watanabe about Misaki's possible connection to the disappearance of her "sister", she remains focused in determining her clone's whereabouts.

Watanabe soon drops off Mikoto at a nearby park, where she is accompanied by members of Misaki's clique who make sure that she cannot leave their presence. Although displeased that she cannot take action against them, Mikoto soon finds an opening when she finds Kuroko, Saten and Uiharu passing by. Immediately, Mikoto discovers that none of the three appear to recognize her. At that moment, Mikoto realizes the extent of Shokuhou Misaki's intervention.

Adapted From

Major Events

  • The first day of the Daihaseisai comes to an end.
  • As Misaka Mikoto tries to find her missing sister, Shokuhou Misaki takes steps to impede and isolate her, including erasing her friends' memories of her.


By order of appearance:

New Characters


New Abilities


New Locations


  • Three unnamed members of Shokuhou Misaki's Clique are voiced by Sasaki Hitomi, Hioka Natsumi, and Yamane Aya.
  • Unnamed female student is voiced by Kazama Mayuko.
  • Unnamed clerk in Heaven Canceller's Hospital is voiced by Iwasaki Ryouta.
  • Unnamed cleaning crew is voiced by Hamaoka Keisuke.
  • Two unnamed paramedic of Fire Station 3 are voiced by Fujii Hayato and Maeda Hiroki.


  • The "Very Valuable Orange" and "Disciplinary Guides" refer to terms used in Toaru Kagaku no Railgun Light Novel Volume SS2 and the Toaru Kagaku no Railgun PSP Game.[1][2]
  • With the advent of the Night Parade and the passing of the first day of the festival, this episode's timeline has passed episode 13 of Toaru Majutsu no Index II.

Cultural References

Entrance to Showa Memorial Park

  • The sentence Auribus Oculi Fideliores Sunt is Latin proverb for "The Eyes Are More Trustworthy Than The Ears". This also becomes the title of the seventh episode in this season.
  • One of the search results shows Bestiaria Latina: Audio Latin Proverbs, which is actually a real blog about Latin proverbs hosted by a teacher of mythology and folklore from the University of Oklahoma, Laura Gibbs. In the present, the blog becomes defunct.[3]
  • Showa Memorial Park (昭和記念公園, Shōwa Kinen Kōen?) is a 160-hectare park located in Tachikawa, Tokyo. It was opened in 1983 to commemorate the 50th anniversary of Emperor Showa's reign.[4]

Differences in Adaptation

  • A short anime-original scene between Misaka Mikoto and Shirai Kuroko is added which introduces the "Tokiwadai students stay at hotels during Daihaseisai" tradition.
  • The shot of what was clearly Shokuhou Misaki's hand reaching for the door of 177th branch of Judgment office was not present in the manga, which just cut from Uiharu discovering something to Mikoto and Kuroko entering the room, meaning the readers at the time had no idea why Uiharu was lying about the website and had deleted the files she downloaded.[5]
  • The episode expands the Night Parade sequence in the manga from a few panels to an entire scene, with the girls looking at the fireworks display from a secret spot.[5]
  • In the manga, Kongou and her father were just standing in the street rather than driving by in a car.[5]

Animation Trivia

  • Several assets originally used during the Night Parade sequence in the 13th episode of Index II are reused in this episode's own Night Parade sequence, though with firework effects and animation.

Unaswered Questions

  • Why did Misaki altered the memory of Kuroko, Uiharu and Saten? Is she truly antagonizing Mikoto?


# Title Time Scene & Notes



This section requires expansion



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