Gigantic revolves around 17-year-old Anna Moore (Grace Gummer) and her younger 16-year-old brother Walt (Tony Oller), two teens who live the lives of Hollywood "it" kids as the children of famous movie star couple John and Jennifer Moore. Anna and Walt have recently returned to Los Angeles after living in Australia for the past two years while their parents were shooting a movie. The series takes a fictional look at the complicated lives of children of Hollywood celebrities, giving an insider view of the glitz, glamour, and A-list parties of Tinseltown. It exposes the life behind the tabloids and gossip blogs, while exploring the difficulties of growing up with superstar parents.
Interestingly, two stars of the series are real-life children of Hollywood celebrities. Grace Gummer is the daughter of Meryl Streep, and Gia Mantegna is the daughter of Joe Mantegna. Plans for the series include celebrity cameo appearances. Oller's character was written to be a musician and he will be performing in several episodes. In real life, Oller is a singer, musician and composer