The film is about Joanne Jet and Cherie Curie, friends who move from rebellious teenagers from Southern California to rock stars in the legendary group. Over time, both friends face a different path of their lives because it is the group that paved the way for future generations of all girls. That group seems to be fully influenced by Svengali-like of the rock impresario Kim Fowley, who turns the group into real success.
In age-appropriate casting, Fanning doesn't put a platform boot wrong in her portrayal of a valley girl rock chick (circa. 1975) growing up way too fast, with neither the inclination nor the wherewithal to slow down.