10 pages | PDF | 2.2 MBMy Once Upon A Time is an upbeat, romantic song from Disney's Descendants 3, composed by David Goldsmith and John Kavanaugh. It has a catchy and light melody, with a driving beat that shows the determination of a lost generation. A minor key change gives the song a bittersweet vibe at the end. My Once Upon A Time has a running time of two minutes and twenty-seven seconds, with eighty-seven measures in the key of G major and E minor. Dove Cameron lends a sweet and soulful voice to the track, helping to bring the story of a lost generation to life.