With her father, drummer Pete Crowne gone, Kathryn "Kat" Crowne becomes an orphan at thirteen. Her new guardian is her father's best friend and also a famous musician who has no time for her. Kat discovers her love of music and eventually forms Neptune with her best friend Thomas. As Neptune gains popularity and Kat matures, she discovers the world in which her parents lived in; sex, drugs and rock & roll. Kat must learn how to stay afloat as temptations cross her path, threatening to unravel everything she has worked so hard to create.