|This article is about a/an episode in Kamen Rider Gaim.|
|WARNING: This episode contains scenes of bloodshed. Viewer discretion is advised!|
The Betrayal of Zangetsu (裏切りの斬月 Uragiri no Zangetsu) is the twenty-eighth episode of Kamen Rider Gaim. This episode marks the debut of Mitsuzane Kureshima becoming the second Kamen Rider Zangetsu Shin, as well as Ryoma Sengoku's first on-screen transformation into Kamen Rider Duke. It also features the final appearance of Gaim Pine Arms and the last time Takatora transforms into Zangetsu Shin in the series.
Takatora reports to Ryoma, Sid, and Yoko that Kouta will be working for them in hunting down the Over Lords in an attempt to stop Helheim Forest. They agree to the plan, but the next time they all enter Helheim Forest, Ryoma has set up a trap to take Takatora out of the equation.
After losing Demushu's trail, Kouta returns to his friends and tells them that Takatora has sided with them with Mitsuzane hiding his displeasure. The next day, though his sister is fine that he does not have a job as he found something that makes him happy, Kouta loses his resumes while he is forced to deal with the Inves.
Luckily, Kouta finds a part-time job at Drupers. In Helheim Forest, as Demushu is being punished for attacking the outsiders, Mitsuzane attempts to kill Kaito to conceal his actions against Kouta. But Kaito explains that while they are enemies, he has no intent to tell Kouta the truth. At the Yggdrasill Corporation, Takatora holds a meeting to discuss hunting down the Over Lords for an alternative to Project Ark. After telling Mitsuzane how Kouta restored his hope for the future, they, Yoko, and Sid depart for Helheim Forest in search for the Over Lords. However, Zangetsu Shin is attacked by Sigurd and Marika as Ryoma arrives to keep him from escaping.
Realizing he has been betrayed by the conspirators, Takatora tells Mitsuzane to report the treachery and help Kouta before he is knocked over a cliff. As Ryoma's group is confident that his older brother is done for, Mitsuzane takes Takatora's Genesis Driver and Melon Energy Lockseed for his own use. After learning there is no one named Takatora working in Yggdrasill, Kouta returns to Druper to serve Kaito until he is tasked to make a delivery at a site where he is ambushed by Mitsuzane as Zangetsu Shin.
With Kaito coming to his aid, Kouta becomes Gaim Kachidoki Arms to stop the fight between Baron Lemon Energy Arms and Zangetsu Shin to find out what is wrong with the latter. Zangetsu Shin refuses to answer and summons a pack of Inves before escaping. Once the Inves are destroyed, Kaito tells Kouta to stop trusting others so easily while leaving him with a warning to be careful of those he thinks are his friends. Back at the Yggdrasill Corporation headquarters, though believing that he would be unopposed in his goal, Ryoma finds that his laboratory has been destroyed by Sid.
Telling Ryoma and Yoko that he only allied himself with them as they had a mutual enemy in Takatora, Sid explains he is going to obtain the Forbidden Fruit as he escapes through the now closing Crack in the sacred tree.
- Kouta Kazuraba (葛葉 紘汰 Kazuraba Kōta): Gaku Sano (佐野 岳 Sano Gaku)
- Mai Takatsukasa (高司 舞 Takatsukasa Mai): Yuumi Shida (志田 友美 Shida Yuumi)
- Kaito Kumon (駆紋 戒斗 Kumon Kaito): Yutaka Kobayashi (小林 豊 Kobayashi Yutaka)
- Mitsuzane Kureshima (呉島 光実 Kureshima Mitsuzane): Mahiro Takasugi (高杉 真宙 Takasugi Mahiro)
- Takatora Kureshima (呉島 貴虎 Kureshima Takatora): Yuki Kubota (久保田 悠来 Kubota Yūki)
- Zack (ザック Zakku): Gaku Matsuda (松田 岳 Matsuda Gaku)
- Peko (ペコ Peko): Saku Momose (百瀬 朔 Momose Saku)
- Ryoma Sengoku (戦極 凌馬 Sengoku Ryōma): Tsunenori Aoki (青木 玄徳 Aoki Tsunenori)
- Lock Dealer Sid (錠前ディーラー シド Jōmae Dīrā Shido): Kazuki Namioka (波岡 一喜 Namioka Kazuki)
- Yoko Minato (湊 耀子 Minato Yōko): Minami Tsukui (佃井 皆美 Tsukui Minami)
- Demushu (デェムシュ Dēmushu, Voice): Tomokazu Sugita (杉田 智和 Sugita Tomokazu)
- Rosyuo (ロシュオ Roshuo, Voice): Jōji Nakata (中田 譲治 Nakata Jōji)
- Akira Kazuraba (葛葉 晶 Kazuraba Akira): Rika Izumi (泉 里香 Izumi Rika)
- Kiyojiro Bando (阪東 清治郎 Bandō Kiyojirō): Tomohisa Yuge (弓削 智久 Yuge Tomohisa)
- Sengoku Driver Equipment Voice (戦極ドライバー各種アイテム音声 Sengoku Doraibā Kanren Aitemu Onsei): Seiji Hiratoko (平床 政治 Hiratoko Seiji)
- Genesis Driver Equipment Voice (ゲネシスドライバー各種アイテム音声 Geneshisu Doraibā Kanren Aitemu Onsei): Shin-ichiro Miki (三木 眞一郎 Miki Shinichirō)
- Narration (ナレーション Narēshon): Hōchū Ōtsuka (大塚 芳忠 Ōtsuka Hōchū)
- Yggdrasill Employee: Kana Ito (伊藤 花菜 Itō Kana)
- to be added
- Lock Used:
- Orange, Pine, Kachidoki
- Lemon Energy
- Zangetsu Shin:
- Melon Energy
- Lemon Energy
- Cherry Energy
- Peach Energy
- Arms Change:
- As part of Super Hero Time, this episode aired alongside Ressha Sentai ToQger episode 11, Station 11: The Emperor of Darkness.
- Viewership: 4.5%
- Closing Screen Lockseed Collection:
- This is the last episode where Takatora transforms into Zangetsu Shin during the run of the TV series.
- When Mitsuzane becomes Zangetsu Shin, he imitates Takatora's grunts, giving the illusion that it is Takatora who is currently Zangetsu Shin.
- The 30th episode takes place after this episode, as explained in the beginning of the said episode.
- This is the first time Kouta transforms directly into Gaim Kachidoki Arms.
- This episode marks the 700th episode of the Heisei era Kamen Rider Series.