Nazo (song)

“Nazo” was released on May 9, 2001, by King Records, following Mizuki's earlier singles “Omoi” and “Heaven Knows.” The song was specifically commissioned as the opening theme for the popular anime series Detective Conan, which was airing on Nippon Television. The collaboration came about through Mizuki's growing presence in the anime music scene, and the single's cover art featured a stylized image of the anime's protagonist, Conan Edogawa. The single reached number 100 on the Oricon weekly chart, a modest debut, but it has since become one of Mizuki's signature songs, often performed at her concerts and included in compilation albums.

Musically, “Nazo” is an upbeat pop-rock track with a driving guitar riff and a catchy, sing-along chorus. The song is written in the key of E major with a tempo of approximately 132 beats per minute. The lyrics, penned by Yasushi Akimoto, revolve around themes of mystery and determination, fitting the detective theme of the anime. The composition by Miki Fujisue blends pop melodies with a slight rock edge, a style that would become characteristic of Mizuki's early work. The arrangement by Yoshimasa Inoue incorporates synthesizers and a prominent bassline, giving the track a polished, late-1990s J-pop production feel.

Although “Nazo” did not achieve high chart positions upon release, it has become a beloved classic among anime fans and Mizuki's fanbase. The song is frequently cited as a gateway for listeners into Mizuki's discography, and it has been included in several of her greatest-hits albums, such as THE MUSEUM (2007). Over the years, “Nazo” has been covered by other artists, including the idol group Kobushi Factory in 2016, and it has been featured in various anime music compilations. The song's enduring popularity is also reflected in its frequent use in karaoke and its presence in fan-made tributes.

Beyond its mainstream success, “Nazo” has several lesser-known facets. The single's B-side, “Kimi to Yumemiru,” is a softer ballad that contrasts with the energetic A-side. Additionally, the song was used as the theme for the Detective Conan video game Nazo no Shinrei Tanteisha (2001), a tie-in that is often overlooked. Mizuki has performed “Nazo” at her annual live tours, but she has noted in interviews that the song's high vocal range makes it challenging to sing live. The song also holds a special place in the history of anime openings, as it was one of the first to be performed by a seiyuu (voice actress) who would later become a major music star, paving the way for other voice actors to pursue singing careers.

Seiyuu

Japanese voice actor or actress, often also involved in music.

Oricon

Japanese music industry ranking chart.