Eureka (Gen Hoshino song)

"Eureka"
Single by Gen Hoshino
from the album Gen
LanguageJapanese
WrittenLate 2024–January 2025
ReleasedJanuary 28, 2025 (2025-01-28)
Studio808 (home studio)
Genre
Length3:31
LabelSpeedstar
Songwriter(s)Gen Hoshino
Producer(s)Gen Hoshino
Gen Hoshino singles chronology
"Why" / "Life"
(2023)
"Eureka"
(2025)
"Fake" (as Akira Nise)
(2025)
Music video
"Eureka" on YouTube

"Eureka" (Japanese pronunciation: [jɯɾꜜːka]) is a song by Japanese singer-songwriter and musician Gen Hoshino from his sixth studio album, Gen (2025). It was released digitally by Speedstar Records on January 28, 2025, as the seventh and last single from the album. As the theme song for the medical drama Diary of a Surgical Resident: Madoka  (2025), Hoshino wrote and produced the track, which takes inspiration from the quiet storm genre and was composed largely within a day. A J-pop and soul ballad with simplistic progression, "Eureka" is about romance and city life. Hoshino sings about his lack of hope despite his despair, before he concludes that uncertainty should be used as a foothold to move forward.

Japanese music critics connected the song's lyrics to the modern way of life and commented on its composition, which two reviewers found simple but detailed. Commercially, "Eureka" reached number 11 on the weekly Billboard Japan Hot 100 and number 33 on the Oricon Combined Singles Chart. The song's music video is composed of scenes of Hoshino that were filmed over a one-week period. It was directed by the single's cover art photographer Kotori Kawashima and features a cameo from actor Taiga Nakano.

Writing

As the theme song for the medical drama Diary of a Surgical Resident: Madoka  (2025), Gen Hoshino began composing "Eureka" using digital audio workstations in late 2024. During production, the song carried the working title "Mountain" in reference to mountain ranges, which had inspired its soundscape. Hoshino conceived "Eureka" as a quiet storm-styled track—slow and mellow, influenced by genres such as soul and jazz. The intro, first verse, chorus, and the arrangement of various instruments were completed within a single day; according to Hoshino, the final track remains largely unchanged from this initial version.[1]

Hoshino approached the song's lyrics, which were written shortly after the New Year, with the intent to create a personal song. On older works, a self-imposed rule prohibited Hoshino from writing about himself, but he wished to create more personal songs after first attempting this on the 2022 single "Comedy".[1] He searched for similarities between his own philosophy and Surgical Resident: Madoka, and remarked on the song's background in a press comment. He recalled that when he was 26-years-old (the same age as the drama's protagonist), he had written a lyric that contained the word wakaranai (わからない; lit.'I don't understand'). Retrospectively, he thought that he never had a moment of understanding/eureka.[1][2]

Composition

"Eureka" is 3 minutes and 31 seconds long.[3] Hoshino produced and programmed the song, and plays bass and synthesizer; Shun Ishiwaka performs on drums and shaker, Hirotaka Sakurada plays standard and digital piano, and Ryosuke Nagaoka features on electric guitar. Hoshino handled recording with Shojiro Watanabe and Shu Saida. Watanabe mixed the song, while Takahiro Uchida mastered it.[4]

"Eureka" is a J-pop song above a repeating beat. It has a middle-tempo soul sound, which Ryūtarō Amano at Mikiki found to be in line with Hoshino's past works like "Comedy", "Ain't Nobody Know" (2019), "Fushigi" (2021), and "Why" (2023).[5][6] A simplistic ballad without bold progression, "Eureka" is opened by Ishiwaka's shaker,[7][8] which is accompanied by piano and drums starting with the first verse. Synthesizer and guitar are featured in the first chorus, where Hoshino's vocals are doubled and the polyphonic background vocals layered. The melody is led by the fusion-styled synth in the aftermath of the chorus, and the bass plays in the background throughout the song.[6] Amano noted influences of quiet storm on the track; he compared its progression to the style of Grover Washington Jr.'s "Just the Two of Us" (1980), and its implementation of a shaker to Sade's "The Sweetest Taboo" (1985). Amano also noted similarities to city pop and album-oriented rock, and influences from Haruomi Hosono on Hoshino's bass.[6]

The lyrics of "Eureka" are about city life and adult romance.[6] Hoshino sings about the unknown, his lack of hope despite the existence of despair, and questions what can be found in a world without hope. Since he has continued to live, he concludes that hope is unnecessary and that uncertainty should be used as a foothold to move forward. He sings "The 'present' carries the past and future",[6][7] and reflects on anxiety and emptiness in lines such as "I bested my sorrows / The fact I'm still breathing / Is proof of that".[5] The pessimistic messages are contrasted by lines that suggest natural imagery: "The seasons dance, clad in the winds and reciting their poetry".[6]

Release and promotion

Cover photographer Kotori Kawashima (pictured left, 2015) directed and filmed the "Eureka" music video, which features a cameo by actor Taiga Nakano (right, 2016).

"Eureka" was first previewed in the first episode of Diary of a Surgical Resident: Madoka on January 14, 2025,[9] before Speedstar Records released the song as a single for download and streaming on Hoshino's 44th birthday: January 28.[10][11] The song's release was promoted with a teaser—a ten-second video clip posted to social media the morning before the premiere of Surgical Resident: Madoka, which featured the text "Gen Hoshino Eureka", played over by what Sports Bull writers called the percussive sound of maracas.[12] The single's cover art, photographed by Kotori Kawashima and designed by Hiromi Fujita, depicts Hoshino covered by sunlight as he stares towards the sky. A phone wallpaper and messaging app stickers based on the artwork were awarded to users who pre-saved the song on streaming platforms.[13] A promotional photo of Hoshino—also handled by Kawashima and Fujita—was unveiled alongside the song's announcement, and would later be used as the cover art for Hoshino's sixth studio album, Gen (2025).[11][14] "Eureka" is the last single released for the album, on which it is the sixteenth and closing track.[15]

Kawashima directed and filmed the "Eureka" music video, which was premiered to YouTube on January 31, 2025.[16] Hoshino invited Kawashima to his studio during the writing of the song; in a one-week time span, they filmed some scenes there and others outside. A cameo appearance is made by actor Taiga Nakano, who meets with Hoshino over a cup of coffee.[17] A behind-the-scenes video, directed and filmed by Koe Inc.'s Yosuke Yamaguchi, was released on March 5, 2025.[18]

Hoshino first performed "Eureka" for a two-hour special of CDTV Live! Live! on February 10, 2025.[19] A minimalistic live version of the song subtitled "808 Sessions"—featuring only Hoshino's soul vocals and digital piano by Hirotaka Sakurada—was uploaded on February 26. It was filmed at Hoshino's home studio 808, where the song and most of the Gen album were also recorded.[20]

Reception

Japanese reviews of "Eureka" praised its lyrics;[7] some critics particularly scored their relevance to modern life.[5][6] Writing for Rockin'On Japan, Hirokazu Koike called "Eureka" a heart-warming song in contrast to the modern "storm of anxiety", and found the lyrics to almost inventively express overlookable truths.[5] In Mikiki, Amano called the song's focus on darkness and despair a grounded form of realism, which he found more relevant to modern way of living in Japan, or the world as a whole, than "delusional hope".[6] Musically, Suzie Suzuki for Yahoo! Japan News described "Eureka" as "pleasant" and "fresh".[21] Amano considered the song a win for fans of Hoshino's musical transition towards middle-tempo soul, though he felt "Eureka" took an approach calmer than some of its preceding works. He found that the sound—a combination of a repeated beat, restrained vocals, and unglamorous progression—resulted in an "intimate" mood of city and night.[6] Koike and Real Sound's Tomoyuki Mori considered the composition simple, but enjoyed Hoshino's attention to detail.[5][7] "Eureka" was nominated for the Drama Song Award at the January–March 2025 The Television Drama Academy Awards. It was the fourth highest-voted song by The Television's journalists and readers, but failed to make the overall top three.[22]

In its week of release, "Eureka" earned 9,440 paid digital downloads according to Billboard Japan, and 2,686,567 streams according to Oricon.[23][24] The song entered at number 11 on the Billboard Japan Hot 100 dated February 5, 2025,[25] and at number 33 on the Oricon Combined Singles Chart dated February 10.[26] The track reached numbers 4 and 44 on Billboard Japan's download and streaming sub-charts, respectively.[23][27] According to radio data surveyist Plantech, "Eureka" was the third most-aired song within its release week. Reporters for their website noted particularly strong performance in regards to listeners' requests, which was more than double of the total received by the other seven songs below it in that week's top ten.[28]

Credits and personnel

Music credits adapted from "Eureka" on Hoshino's official website, except where otherwise cited;[4] visual personnel taken from video description on YouTube[16]

Music and production
Music video
  • Kotori Kawashima – direction, videography, editing
  • Shintaro Tamada – assistant direction, editing
  • Yohei Kawada – creative direction, production
  • Jin Otabe – assistant production
  • Yosuke Yamaguchi (Koe Inc.) – behind-the-scenes videography
  • Ryotaro Takahashi – online editing
  • Matawe Wongpuak – online editing
  • Tomokazu Saito – multi-audio engineer
  • Hiromi Fujita – title design
  • Dai Ishii – styling
  • Shuto Sugiyama – assistant styling
  • Rumi Hirose – hair-styling
  • Miyuu Takeuchi – hair-styling
  • Masaki Takahashi – hair-styling for Taiga
  • Gen Hoshino – cast
  • Taiga Nakano – cameo

Charts

Weekly chart performance for "Eureka"
Chart (2025) Peak
position
Japan Hot 100 (Billboard Japan)[29] 11
Japan Combined Singles (Oricon)[30] 33

Release history

Release date and formats for "Eureka"
Region Date Format(s) Label Ref.
Various January 28, 2025 Speedstar Records [10]
South Korea J-Box Entertainment [31][32]

References

  1. ^ a b c Hoshino, Gen (February 3, 2025). 希望は要らないまま──「Eureka」インタビュー [When Hope Is Unneeded — "Eureka" Interview]. Yellow Magazine+ (Interview) (in Japanese). Archived from the original on February 7, 2025. Retrieved February 7, 2025.
  2. ^ 星野源が新ドラマ「まどか26歳、研修医やってます!」主題歌書き下ろし [Gen Hoshino Writes Theme Song to New Drama Diary of a Surgical Resident: Madoka]. Natalie.mu (in Japanese). January 8, 2025. Retrieved January 14, 2025.
  3. ^ "'Eureka' - Single by Gen Hoshino". Spotify (Japan). n.d. Retrieved March 4, 2025.
  4. ^ a b "'Eureka'". HoshinoGen.com. n.d. Archived from the original on January 27, 2025. Retrieved January 27, 2025.
  5. ^ a b c d e Koike, Hirokazu (February 28, 2025). 生きることに腹を括ったポップソング [A Pop Song with Courage to Live]. Rockin'On Japan (in Japanese). Archived from the original on March 4, 2025. Retrieved March 4, 2025.
  6. ^ a b c d e f g h i Amano, Ryūtarō (February 18, 2025). 星野源"Eureka"のサウンドと歌詞を考察 抑制されたクワイエットストーム、そして不確かな〈わからなさ〉と確かな絶望 [Examining the Sound and Lyrics of Gen Hoshino's "Eureka" — A Restrained Quiet Storm, the Uncertain "Unknown", and Despair]. Mikiki (in Japanese). Archived from the original on March 4, 2025. Retrieved March 4, 2025.
  7. ^ a b c d Tomoyuki, Mori; Ishii, Eriko (January 31, 2025). 星野源、米津玄師、Number_i、Ado、Creepy Nuts、乃紫……注目新譜6作をレビュー [Gen Hoshino, Kenshi Yonezu, Number_I, Ado, Creepy Nuts, Noa... Six New Releases in Focus]. Real Sound (in Japanese). Archived from the original on February 17, 2025. Retrieved March 4, 2025.
  8. ^ 星野 源の新曲「Eureka」に石若 駿が参加 [Shun Ishikawa Features on New Gen Hoshino Song "Eureka"]. Rhythm & Drums Magazine (in Japanese). January 28, 2025. Archived from the original on February 23, 2025. Retrieved March 4, 2025.
  9. ^ 星野源、ドラマ『まどか26歳、研修医やってます!』主題歌「Eureka」配信リリース [Gen Hoshino to Release New Single, Diary of a Surgical Resident: Madoka Drama Theme Song "Eureka"]. Billboard Japan (in Japanese). January 14, 2025. Archived from the original on January 14, 2025. Retrieved January 14, 2025.
  10. ^ a b 星野源 — Eureka (VE3WT-11501) [Gen Hoshino — "Eureka" (VE3WT-11501)] (in Japanese). Victor Entertainment. n.d. Retrieved March 7, 2025.
  11. ^ a b 星野源が44歳の誕生日に新曲リリース、川島小鳥撮影の新アーティスト写真も公開 [Gen Hoshino to Release New Song on 44th Birthday, Unveils New Artist Visual by Kotori Kawashima]. Natalie.mu (in Japanese). January 14, 2025. Archived from the original on January 14, 2025. Retrieved January 14, 2025.
  12. ^ 「マラカス…?」星野源が投稿した謎の動画にファン歓喜 [Maracas...? Fans React to New Mysterious Video Posted by Gen Hoshino]. Sports Bull (in Japanese). January 14, 2025. Archived from the original on January 14, 2025. Retrieved January 14, 2025. Select 記事全文を見る for full article
  13. ^ a b c 星野源、新曲「Eureka」配信アートワーク公開 リスニングパーティ&配信キャンペーンも [Gen Hoshino Unveils "Eureka" Cover Artwork, Announces Listening Party and Digital Campaigns]. Musicman (in Japanese). January 24, 2025. Retrieved January 24, 2025.
  14. ^ 星野源、ニューアルバム『Gen』のジャケットアートワーク公開 [Gen Hoshino Unveils Cover Artwork to New Album Gen]. The First Times (in Japanese). March 24, 2025. Retrieved April 23, 2025.
  15. ^ 星野源「Gen」トラックリスト公開 カミーロ、イ・ヨンジ、コーデーら参加 [Tracklist to Gen Hoshino's Gen Includes Camila, Lee Young-ji, Cordae, and More]. Natalie.mu (in Japanese). April 23, 2025. Retrieved April 23, 2025.
  16. ^ a b Gen Hoshino — "Eureka" (Official Video) (Media notes). Gen Hoshino. January 31, 2025. Archived from the original on January 31, 2025. Retrieved March 4, 2025 – via YouTube. Expand description for credits
  17. ^ 星野源、新曲「Eureka」MV公開 仲野太賀出演&川島小鳥監督、楽曲制作に寄り添った1週間を収める [Gen Hoshino Releases Music Video to New Song "Eureka" featuring Taiga Nakano and Director Kotori Kawashima]. Real Sound (in Japanese). January 31, 2025. Archived from the original on February 9, 2025. Retrieved February 7, 2025.
  18. ^ 星野源、最新曲「Eureka」MVのメイキング映像を公開 [Gen Hoshino Shares Behind-the-Scenes to "Eureka" Music Video]. Barks (in Japanese). March 5, 2025. Archived from the original on March 5, 2025. Retrieved February 7, 2025.
  19. ^ Citations regading performance of "Eureka" on CDTV Live! Live!:
  20. ^ 星野源、全国アリーナツアー追加公演決定! 新曲「Eureka」セッション動画を公開 [Gen Hoshino Adds New Shows to National Arena Tour, Releases "Eureka" Session Video]. The First Times (in Japanese). February 26, 2025. Archived from the original on March 4, 2025. Retrieved March 4, 2025.
  21. ^ Suzuki, Suzie (February 28, 2025). 星野源「Eureka」から考える、Jポップに「サビ」がなくなる日【月刊レコード大賞】 [Monthly Record Award: Based on Gen Hoshino's "Eureka", the Day Choruses Disappear from J-Pop]. Yahoo! Japan News (in Japanese). Archived from the original on March 7, 2025. Retrieved March 9, 2025.
  22. ^ 第123回ザテレビジョンドラマアカデミー賞 [123rd The Television Drama Academy Awards — Drama Song Award]. The Television (in Japanese). March 2025. Retrieved June 2, 2025.
  23. ^ a b Number_i「GOD_i」DLソング首位デビュー 米津玄師の最新曲が2位に続く [Number_I's "God_I" Debuts Atop Download Songs, Kenshi Yonezu's Newest Song at Number Two]. Billboard Japan (in Japanese). February 5, 2025. Retrieved March 9, 2025.
  24. ^ ストリーミング週間50 — 2025年02月10日付 [Weekly Streaming Top 50 — February 10, 2025] (in Japanese). Oricon. February 10, 2025. p. 5. Archived from the original on February 7, 2025. Retrieved March 9, 2025.
  25. ^ Number_i「GOD_i」が総合首位、米津玄師「BOW AND ARROW」は4位デビュー [Number_I's "God_I" Tops Hot 100, Kenshi Yonezu's "Bow and Arrow" Debuts at Number Four]. Billboard Japan (in Japanese). February 5, 2025. Retrieved March 9, 2025.
  26. ^ 合算シングル週間50 — 2025年02月10日付 [Weekly Combined Singles Top 50 — February 10, 2025] (in Japanese). Oricon. February 10, 2025. p. 4. Archived from the original on February 7, 2025. Retrieved March 9, 2025.
  27. ^ "Gen Hoshino Chart History (Streaming Songs)". Billboard Japan (in Japanese). n.d. Archived from the original on January 19, 2024. Retrieved March 9, 2025. Select Streaming Songs on the dropdown menu under 週間チャート
  28. ^ ミセス"18祭"曲で1位 / Number_i初登場2位 / 星野源 圧倒的リクエスト数の3位 [Mrs. Green Apple Number One with 18-sai Theme Song, Number_I Debuts at Number Two, and Gen Hoshino Sweeps User Requests at Number Three]. Plantech (in Japanese). February 5, 2025. Archived from the original on May 3, 2025. Retrieved May 3, 2025.
  29. ^ "Gen Hoshino Chart History (Hot 100)". Billboard Japan (in Japanese). n.d. Archived from the original on January 19, 2024. Retrieved March 4, 2025. Select Hot 100 on the dropdown menu under 週間チャート
  30. ^ 星野源の合算シングル売上TOP12作品 [Gen Hoshino's Top 12 Combined Singles by Sales] (in Japanese). Oricon. n.d. Archived from the original on February 6, 2025. Retrieved March 4, 2025.
  31. ^ "Eureka" — Gen Hoshino (호시노 겐/星野 源) (in Korean). Melon. n.d. Archived from the original on May 3, 2025. Retrieved May 3, 2025.
  32. ^ "Eureka" — Gen Hoshino (호시노 겐/星野 源) (in Korean). Bugs!. n.d. Archived from the original on May 3, 2025. Retrieved May 3, 2025.