Under Ninja

• Ja Kanji — アンダーニンジャ • Ja Romaji — Andā Ninja • Genre — Action, comedy

• Type — manga • Author — Kengo Hanazawa • Publisher — Kodansha • Imprint — Young Magazine KC • Magazine — Weekly Young Magazine • First — July 23, 2018 • Volumes — 18

• Type — tv series • Director — Satoshi Kuwabara • Writer — Keiichirō Ōchi • Music — Shōta Kowashi • Studio — Tezuka Productions • Licensee — Crunchyroll • Network — TBS, BS11 • First — October 6, 2023 • Last — December 22, 2023 • Episodes — 12

• Type — live film • Director — Yūichi Fukuda • Writer — Yūichi Fukuda • Released — 2025 01 24

• Portal — yes Under Ninja is a Japanese manga series written and illustrated by Kengo Hanazawa. It has been serialized in Kodansha's Weekly Young Magazine since July 2018. An anime television series adaptation by Tezuka Productions aired from October to December 2023. A live-action film adaptation premiered in Japanese theaters in January 2025.

The ninja organization in Japan, which once flourished, was dismantled by the GHQ after the Pacific War and disappeared. However, the ninja still exist in secret, and it is said that there are 200,000 of them living in Japan today, hiding and working in the dark in the public and private sectors and in all kinds of organizations. While some of the elite ninja work behind the scenes in national level conflicts, the ninja at the end of the line are often unable to find work. One of them, Kuro Kumogakure, who is living the life of a NEET, receives a serious "ninja assignment," an order from his superiors to infiltrate a high school with the latest equipment.

• Kurō Kumogakure • Taito Ban • Kento Yamazaki • Katō • Tarusuke Shingaki • Shotaro Mamiya • Hibi Mirakuru • Tasuku Hatanaka • Suzuki • Atsumi Tanezaki • Mai Shiraishi • Shion Hachiya • Daiki Yamashita • Ryubi Miyase • Kawado • Chika Anzai • Haruka Kinami • Ōno: • Tsuyoshi Muro • Eita • Shūichi Uchida • Ryо̄tarо̄ Sakaguchi • Noguchi • Sora Tokui • Minami Hamabe • Ozu • Kōichi Sōma • Saruta • Amane Okayama • Mitsuki Yamada • Chihiro Yamamoto • Principal • Mitsuru Hirata • Homeroom Teacher • Shinobu Hasegawa • Akikazu Yoshida • Jiro Sato

Under Ninja, written and illustrated by Kengo Hanazawa, started in Kodansha's seinen manga magazine Weekly Young Magazine on July 23, 2018. Kodansha has collected its chapters into individual tankōbon volumes. The first volume was released on February 6, 2019. As of August 6, 2026, 18 volumes have been released. In North America, Denpa announced the English language release of the manga in July 2020.

On September 6, 2021, it was announced that the series would receive an anime television series adaptation. It is produced by Tezuka Productions and directed by Satoshi Kuwabara, with scripts supervised by Keiichirō Ōchi, character designs by Nobuteru Yūki, and music composed by Shōta Kowashi. The series aired from October 6 to December 22, 2023, on TBS and BS11. The opening theme song is "Hyper" by Kroi. Crunchyroll streamed the series outside of Asia.

Under Ninja is associated with Japan.