Yamashita previously created the beautiful theme song Bokura no Natsu no Yume for Hosoda’s 2009 film Summer Wars (an acoustic live version of that song is included on this single). For Mirai, he made the theme song Mirai no Theme (“Theme of Mirai”) and ending theme Uta no Kisha (“Music Train”), which are delightful treats for both fans of his music and film audiences. Hosoda’s charming film follows a small boy named Kun and his many feels after the arrival of a baby sister who usurps his parents’ attention. Between mischievous episodes and tearful tantrums, he wanders through flights of fantasy about his dog in human form, his mother’s childhood and his teenaged sister from the future who has come to see him. His sister’s name of Mirai sounds the same as the Japanese word for “future.”
Without the film as context, Mirai no Theme sounds like an affectionate love song with its sugary calls of “My Baby Girl,” “Cute! Cute!” and “Sweet! Sweet!” The song takes on even sweeter meaning, though, with the knowledge that the film’s Mirai is an actual baby girl. The uplifting declaration of “Our love finally just started now / Towards the future” refers to not just the standard romantic love of pop songs, but a familial love and hope for the future.
Mirai no Theme‘s endearing message is matched by a light and pleasant pop melody that simply lifts spirits. Even before Yamashita starts singing in his silky, soothing voice that tells stories, the sprightly tempo and jaunty beats already have you hooked. The song has a nostalgic quality to it, especially its saxophone section, such that it feels like it could have been released any time in the last few decades.
In Mirai, Kun-chan loves trains, and Yamashita uses this detail as the theme of Uta no Kisha. The song begins fittingly with the sound of a train whistle and sets off on life’s journey with a bright yet melancholic melody. The “music train” chugs along on pronounced beats and wistful, winsome lyrics like “Tonight’s music train, small party train / I’m coming for you.” Yamashita’s vocals are very expressive in this song, especially the way he curls and swallows notes in the bridge and emphasizes the words before “train” in the refrain. Like Mirai no Theme, Uta no Kisha has a cozy city pop vibe that just may take you on a train trip down memory lane.