Only child Julia Bechley finds her life turned upside down when her father, Leon, reveals that, over the course of his prize-winning career as a pioneering fertility doctor, he used his own sperm to conceive upwards of a hundred children. Reeling from this explosive revelation, Julia discovers two new sisters – her former best friend, Edie Palmer, and an ex-Olympic athlete, Roxy Doyle. As these three young women begin to embrace their new reality, Julia must figure out what life is like without Leon by her side; Edie comes to grips with her burgeoning sexuality, as her marriage falters; and Roxy faces adulthood out of the spotlight. Against all odds, the three women will attempt to form an untraditional bond as sisters, even as they must welcome a tidal wave of new siblings into their rapidly expanding family. Based on the Australian series "Sisters".