Back Number have never written a song for another artist before, and Shimizu shared in a press release that his exchange with BTS — in particular Jungkook, who suggested a new melody based on the demo Shimizu sent — was an exciting experience.
“I had some reservations because I’d never written a song that someone else besides myself would sing,” Shimizu said. “But I’m happy that we’ve completed a very lyrical, yet powerful track thanks to our experienced staff, our co-arranger UTA’s efforts, some exciting exchanges with Jungkook, and the personal qualities and power of expression each of the BTS members have.”
Previously, BTS’s “Don’t Leave Me” was featured as the theme of the Japanese TV drama Signal, a remake of a South Korean series by the same name, starring Kentaro Sakaguchi as a police officer who communicates with another officer from the past to crack unsolved cases.
The members of BTS noted in the release that they were happy to be tapped again for the “scaled-up” feature film version, and that they were drawn to the new theme’s melody when they first heard it.
“The new song ‘Film Out’ is a track we wrote together with Back Number, and we were drawn to the beautiful melody when we first received the demo from Mr. Shimizu,” they shared. “We fell in love with the song while we were working on it, so we hope you all like it, too. It’s a ballad with a poignant melody and lyrics, and we’re sure it has the power to touch many people’s hearts. Please enjoy our song along with the movie.”
SIGNAL The Movie Cold Case Investigation Unit will open in Japanese theaters on April 2.