The five members of Tűz és Jég—Sebastian, Claude, Sam, Greg, and Nathan—have been making music together for five years and are inseparable friends both on and off the stage. Sebastian’s eighteen-year-old younger sister, , visits them during one of their rehearsals and watches the boys from behind the curtain. While listening to Sebastian sing, quietly begins singing along, unaware that the boys can hear her voice. The band members are surprised by her beautiful voice and immediately want to convince her to sing for them again. Could ’s hidden talent open a new chapter in Tűz és Jég’s story, and perhaps make her the band’s sixth voice?