Hikaru Utada, Kenshi Yonezu deliver pop perfection with collab hit 'Jane Doe'

Chainsaw Man – The Movie: Reze Arc premiered September 19, racking up nearly three billion yen (USD $20 million) in box office receipts in its first 10 days. The film follows the story of teenage devil hunter Denji and his encounter with a mysterious girl named Reze; it serves as a continuation of the Chainsaw Man anime series based on the manga of the same name, which has sold over 100 million copies globally to date.

Such a massively popular franchise demands performers equally as influential for its film soundtrack – enter Kenshi Yonezu and Hikaru Utada, easily two of Japan's biggest pop stars. The unexpected duo team up for the first time to perform the film's ending theme, 'Jane Doe'.

The track was written and composed by Yonezu, who's been a veritable force in the music industry for over a decade and boasts numerous accolades. He recently received even more recognition, as his 2022 track 'Kick Back', the opening theme for the Chainsaw Man series, was certified Platinum by the Recording Industry Association of America (RIAA) just last month. It's the first Japanese-language song to earn the certification, so it's no surprise that Yonezu was called back to write for the Chainsaw Man film.

Yonezu co-produced 'Jane Doe' with previous collaborator Yaffle and tagged the one and only Hikaru Utada as co-vocalist. As one of the most successful music artists in Japan, whose 1999 album First Love remains the best-selling album in Japanese music history to this day, Utada was the perfect choice to elevate Yonezu's already exceptional work to the next level.

'Jane Doe' is a brooding ballad that waltzes along in 6/8 at a steady 128 bpm, its opening progression of minor and diminished piano chords saturating the track with a bittersweet melancholy before the lyrics have even begun. Skillfully crafted piano- and string-centred instrumentals play over jazzy bass and percussion, courtesy of the airtight production expected of a Yonezu track.

Hikaru sings solo for the first verse and chorus, their soulful vocals fully owning every second of the mournful melody. The undeniable gravity of Hikaru's presence permeates throughout the entire song – so much so that at times it almost feels as though Kenshi is one misstep away from becoming a feature in his own song, but he manages to hold his own alongside the veteran vocalist. Hikaru masterfully delivers Kenshi's ever-evocative lyrics, embodying the titular Jane Doe and beseeching the listener to follow her bloodied red footsteps as she walks barefoot on broken glass.

The second verse is Kenshi's domain, in which picturesque lines of goldfish released into rusty pools and apples hidden in shoeboxes build upon the track's mystique, all while Kenshi flaunts another of his trademark talents: his extraordinary vocal range.

The versatile singer effortlessly spans two whole octaves in a single verse, and the subsequent call-and-response and harmonising moments between him and Hikaru – Where are you? (I'm here.) What are you doing? (I've always been watching over you.) – are just as flawless in their execution.

Hikaru drives things forward with another solo chorus, after which the song soars to new heights in the refrain, a crescendo of raucous synths adding an unapologetic grit to the mix. The ensuing adlibs between Hikaru and Kenshi during the outro are nothing short of otherworldly, making the song's slightly longer-than-average 3:56 runtime well worth the wait. After the climax, we're back where we started: a progression of pensive piano chords closes us out, trailing off into silence.

The accompanying music video is directed by Tomokazu Yamada, who has previously collaborated with both artists on multiple projects, including the music video for Yonezu's 2018 mega-hit 'Lemon' and Utada's 2025 single 'Mine or Yours'. In those works, as in many of his others, Yamada's style utilises simple yet powerful visuals that manage to be attention-grabbing without feeling contrived or overly flashy. 'Jane Doe' is no exception.

We begin with Hikaru lying down on a rotating double-sided bench in a dimly lit metro station, but shot at an impressively dizzying 90-degree angle – perhaps a nod to the film's own 'Jane Doe' and the disorientating nature of her inner turmoil. Later we're right-side up as Kenshi joins Hikaru on the bench (the latter dressed all in black, the former in black and grey), but they're on opposite sides, never touching or even acknowledging one another as trains rush by in both directions.

Glass shards fall from above in the climax, and, just like the song itself, the video ends how it began: Utada lying down on the rotating bench, alone. Simple and clean, Yamada beautifully encapsulates the themes of the song and film while successfully navigating the tightrope of showcasing neither too much nor too little of the two megastars present. (Watch the music video below.)

'Jane Doe' is currently ranked #2 on the Billboard Japan Hot 100 and #90 on the Billboard Global 200, with upwards of 9.4 million streams on Spotify. By comparison, the Chainsaw Man film's opening theme – entitled 'Iris Out', also composed and performed by Yonezu (sans Utada) – is #1 on the Japan Hot 100 and soared from a debut spot of #32 globally upon release to its current position of #5, with over 30 million streams on Spotify.

Time will tell whether 'Jane Doe' will rise in international popularity, but even if the film's sombre ending theme doesn't manage to reach the heights of its up-tempo companion track, the song has nonetheless solidified itself as a momentous event in pop music history.

Hikaru's grounded, heartfelt performance allied with Kenshi's spectacular range and meticulous vocal precision creates a striking contrast of light and shadow that somehow just works – here's hoping for more collaborations in the future. In the meantime, we've got this one on repeat.

Chainsaw Man – The Movie: Reze Arc is now in theatres nationwide.