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IMDbPro

Ryû Manatsu

  • Actor
  • Producer
  • Soundtrack
IMDbProStarmeterSee rank
Ryu Manatsu is a Japanese actor, singer and voice actor. His real name is Mikio Seto. He is best known for his role as Gen Otori, the main protagonist and human form of Ultraman Leo (1974). He also sang the theme song and two insert themes for Ultraman Leo (1974) and is a member of the Ultraman Foundation.

Manatsu had dreamed of becoming an actor since childhood, greatly influenced by his high school senior, Kyu Sakamoto. With the goal of becoming an actor, he started his career as a singer at a club in Yokohama. In 1972, Manatsu made his debut in television dramas under his real name, Mikio Seto.

In 1974, Manatsu was selected to play the lead role of Gen Otori in Ultraman Leo (1974). At the time, he was introduced by director Tadashi Mafune, who had visited his club as a guest. Mafune then arranged for Manatsu to meet with Tsuburaya Productions producer Ken Kumagai and TBS's Yôji Hashimoto for a five-minute casting interview. The decision to cast Manatsu as the lead was made on the same day. It is said that Manatsu was chosen because of his previous experience in practicing Shorinji Kempo, which made him capable of performing action scenes, a decisive factor in the selection process.

The filming of the early episodes of Ultraman Leo (1974) was a very intense and difficult experience for Manatsu, with the training that Dan Moroboshi gives to Gen proving painful and difficult to enact. During the filming of episode 8, he was paralyzed from the waist down because of a scene in which Gen sits under a waterfall in the freezing cold.

Afterward, Manatsu continued to appear in numerous television dramas and films, and he worked as a producer at the anime company Staff 21 as an animation producer under his real name. After Staff 21 ceased operations, he returned to acting, taking on supporting roles in various TV series, including historical dramas and Taiga dramas, while also becoming active as a voice actor in anime.

In 2004, he was diagnosed with terminal-stage stomach cancer, but after undergoing treatment, he overcame the illness and fully recovered. Since 2006, he has been actively participating in events related to the Ultraman Series. Alongside his acting career, Manatsu has also collaborated with the Agency for Cultural Affairs' Performer Dispatch Program, giving folklore lectures at kindergartens, elementary schools, junior high schools, and high schools.
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  • Known for

    Ultraman Mebius (2006)
    Ultraman Mebius
    8.1
    TV Series
    • Gen Otori
    • Ultraman Leo
    Ultraman Saga (2012)
    Ultraman Saga
    6.3
    • Gen Otori
    • 2012
    Ultraman Leo (1974)
    Ultraman Leo
    7.3
    TV Series
    • Gen Ôtori
    • Ultraman Leo
    Engine Sentai Go-onger (2008)
    Engine Sentai Go-onger
    6.5
    TV Series
    • Toujirou Fuji

    Credits

    IMDbPro

    Actor



    • Kaiju Mono (2016)
      Kaiju Mono
      5.7
      • Doctor Saigo
      • 2016
    • The Phantom Thief YAMANEKO (2016)
      The Phantom Thief YAMANEKO
      6.8
      TV Series
      • 2016
    • Outer Man (2015)
      Outer Man
      6.3
      • Chief of Staff Oshima
      • 2015
    • Atsushi Itô, Hideaki Itô, and Hidetoshi Nishijima in Painless (2015)
      Painless
      6.5
      TV Mini Series
      • 2015
    • Yutaka Mizutani and Takashi Sorimachi in Aibou: Tokyo Detective Duo (2000)
      Aibou: Tokyo Detective Duo
      8.1
      TV Series
      • Koshiro Ueno
      • 2011–2015
    • Yoshiwara Uradôshin (2014)
      Yoshiwara Uradôshin
      TV Mini Series
      • 2014
    • Ultraman Saga (2012)
      Ultraman Saga
      6.3
      • Gen Otori
      • 2012
    • Ultra Galaxy Legend Side Story: Ultraman Zero vs. Darklops Zero - Stage II: Zero's Suicide Zone
      6.9
      Video
      • 2010
    • Ultra Galaxy Legend Side Story: Ultraman Zero vs. Darklops Zero - Stage I: Cosmic Collision
      7.0
      Video
      • 2010
    • Mega Monster Battle: Ultra Galaxy Legends - The Movie (2009)
      Mega Monster Battle: Ultra Galaxy Legends - The Movie
      7.0
      • Ultraman Leo (voice)
      • 2009
    • Jôô Virgin (2009)
      Jôô Virgin
      4.8
      TV Series
      • Kouzou Tsukishima
      • 2009
    • Kurema - Case 1 (2008)
      Kurema - Case 1
      Video
      • Detective
      • 2008
    • Engine Sentai Go-onger (2008)
      Engine Sentai Go-onger
      6.5
      TV Series
      • Toujirou Fuji
      • 2008
    • All Is Fine (2007)
      All Is Fine
      7.4
      TV Series
      • Masaru Mochizuki
      • 2007
    • Onsen maruhi daisakusen! 4: Noto hantô Wajima onsen wo meguru kyûkyoku no zuwaigani to dentô no waza Wajima-nuri no bi ni kakusareta renzoku satsujin no nazo! (2007)
      Onsen maruhi daisakusen! 4: Noto hantô Wajima onsen wo meguru kyûkyoku no zuwaigani to dentô no waza Wajima-nuri no bi ni kakusareta renzoku satsujin no nazo!
      TV Movie
      • Ryuji Tanahashi - Hotel Koshuen board chief
      • 2007

    Producer



    • Dodge Danpei (1991)
      Dodge Danpei
      7.2
      TV Series
      • producer (as Mikio Seto)
      • 1991–1992
    • Dash! Yonkuro (1989)
      Dash! Yonkuro
      6.8
      TV Series
      • associate producer (as Mikio Seto)
      • 1989–1990

    Soundtrack



    • Ultraman Leo (1974)
      Ultraman Leo
      7.3
      TV Series
      • performer: "Urutoraman Reo"
      • 1974–1975

    Personal details

    • Official site
      • X
    • Alternative names
      • Ryugo Manatsu
    • Height
      • 5′ 7″ (1.70 m)

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