One Voice tells the story of the Kamehameha Schools Song Contest through the eyes of the student song directors. Every year in Hawai’i, 2000 high school students compete in the Kamehameha Schools Song Contest where young leaders direct their peers in singing Hawaiian music in four-part harmony. One Voice shares the thrill of the competition via the personal stories of the student song directors as they experience the trials and tribulations of competition in this annual high school event.