|This article is about a/an episode in Juken Sentai Gekiranger.|
Twenty-third Lesson - Gure-Gure! Gure-Gure! Sukeban Captain (グレグレ！スケ番キャプテン Gure-Gure! Sukeban Kyaputen) is the twenty-third episode of Juken Sentai Gekiranger. It further introduces the mysterious Gou Fukami after his cameo in the previous episode while likewise introducing another mysterious newcomer: a strange man known as Long.
Ran's new position as Gekiranger captain is thrown into doubt when a Beast-Man transforms her into a heartless bad girl.
Shafu believes that with another Gekiranger coming, a team captain is necessary and he selects Ran to be that suitable leader. She tries to teach some sense into Jan and Retsu by reviewing their past battles until Rin Jū Porcupine-Ken user Mārashiya begins his attack on the city. Ran tries to order Jan and Retsu in the battle, but they are attacked and Ran is hit by Mārashiya's Ringi Needle-Sword Mountain, turned into a sukeban with no cure in sight. She wreaks havoc in the SCRTC office, with everyone attempting to restraint her in vain as she jumps out of the building, taking off on a motorcycle while Natsume watches. But while the rest of the group tries to figure out what to do, Jan and Retsu run off to intercept Mārashiya, briefly encountering a werewolf who went after Retsu before eluding. No sooner did the werewolf leave then Mārashiya arrive and the two Gekirangers fight him. Meanwhile, being a sukeban in her youth, Miki tracks Ran in an underground club, easily taking her down and dragging her back to SCRTC to force her to remember her heart and regain her old self, allowing Ran to help Jan and Retsu, as well as have her use her Kageki to burn the Ringi off her. The Gekiranger managed to destroy Mārashiya by using Ran's experience as a Sukeban in the new GekiElephantFire formation. While this all occurs, Maku overthrows Rio while showing off his Dorinki, which Rio is determined to learn at the cost of his dignity. A sadden Mele would leave the chamber and be confronted the mysterious Long, who offers her good news. Back in Tokyo, after making their peace, the Gekirangers see the werewolf, who reverts to human form. Then the figure turned around, Retsu realizes that it is his supposedly dead older brother: Gou Fukami.
- Jan Kandou (漢堂 ジャン Kandō Jan): Hiroki Suzuki (鈴木 裕樹 Suzuki Hiroki)
- Ran Uzaki (宇崎 ラン Uzaki Ran): Mina Fukui (福井 未菜 Fukui Mina)
- Retsu Fukami (深見 レツ Fukami Retsu): Manpei Takagi (高木 万平 Takagi Manpei)
- Gou Fukami (深見 ゴウ Fukami Gō): Riki Miura (三浦 力 Miura Riki)
- Master Sha-Fu (マスター・シャーフー Masutā Shā Fū, Voice): Ichirō Nagai (永井 一郎 Nagai Ichirō)
- Miki Masaki (真咲 美希 Masaki Miki): Kazue Itoh (伊藤 かずえ Itō Kazue)
- Elehung Kam Po (エレハン・キンポー Erehan Kinpō, Voice): Yū Mizushima (水島 裕 Mizushima Yū)
- Michelle Peng (ミシェル・ペング Misheru Pengu, Voice): Atsuko Tanaka (田中 敦子 Tanaka Atsuko)
- Natsume Masaki (真咲なつめ Masaki Natsume): Sakina Kuwae (桑江 咲菜 Kuwae Sakina)
- Rio (理央 Rio): Hirofumi Araki (荒木 宏文 Araki Hirofumi)
- Mele (メレ Mere): Yuka Hirata (平田 裕香 Hirata Yuka)
- Sky Fist Demon Kata (空の拳魔カタ Sora no Kenma Kata, Voice): Rokurō Naya (納谷 六朗 Naya Rokurō)
- Sea Fist Demon Rageku (海の拳魔ラゲク Umi no Kenma Rageku, Voice): Naoko Kouda (幸田 直子 Kōda Naoko)
- Land Fist Demon Maku (大地の拳魔マク Daichi no Kenma Maku, Voice): Hidekatsu Shibata (柴田 秀勝 Shibata Hidekatsu)
- Long (ロン Ron): Naoki Kawano (川野 直輝 Kawano Naoki)
- Marashiya (マーラシヤ Mārashiya, Voice): Takayuki Kondō (近藤孝行 Kondō Takayuki)
- SCRTC Member: Satoshi Morota (諸田 敏 Morota Satoshi)
- to be added
- As part of Super Hero Time, this episode aired alongside Kamen Rider Den-O episode 27, Schedule-Disrupting Fang.
- Pre-Credits: GekiElephantFire.
- As of this episode, Ran becomes the official leader of the Gekirangers.
Juken Sentai Gekiranger Volume 6 features episodes 21-24: Lesson 21: Biki-Biki-Biki-Biki! Kageki in Extreme Ki, Lesson 22: Kyui-Kyui! Date with a Celebrity, Lesson 23: Gure-Gure! Gure-Gure! Sukeban Captain, and Lesson 24: Garu-Garu! What!? You're my Younger Brother!?. 
- Bad to the Bone - Power Rangers counterpart in Jungle Fury. See comparison page.
- Fear and the Phantoms - Power Rangers counterpart in Jungle Fury. See comparison page. (Long's debut)