Christina is an American actress and dancer who begins working as a child to help support her mother. She grows up in a chaotic Laurel Canyon environment, utilizing television sets and dance studios as safe havens from domestic instability. She maintains a public persona of a confident, funny performer while privately managing severe self-esteem issues and physical pain.

Nancy is a talented singer-songwriter and Christina's mother. Left to raise her daughter alone after her husband's departure, she self-medicates her anxiety with drugs and falls into a severe addiction. She struggles to provide stability but consistently offers her daughter deep affection and a feeling of maternal safety.

Bob is Christina's father who abandons the family shortly after his daughter is born. He starts a new life and a new family elsewhere, leaving his ex-wife and infant to fend for themselves in Los Angeles. He carries unexamined wounds from his own difficult upbringing with a harsh father.

Joe is a successful percussionist who works with famous rock bands and dates Nancy. He introduces her to heroin as a sleep aid, triggering her long-term struggle with addiction. He creates a highly volatile, violent household that forces young Christina to mature quickly.

Martyn is a punk rock musician who immediately captures Christina's attention. They share a profound, instant connection during their first brief encounter. He weaves in and out of her life over the years, eventually offering a grounding, supportive presence.

David is an actor who befriends Christina during her time on the popular sitcom. He steps in as a protective figure when she needs physical and emotional help to safely exit a dangerous domestic situation.

David works alongside Christina for years on the Fox sitcom. He acts as a supportive peer and changes the course of her life by convincing her to take a vacation to Maui, introducing her to her favorite sanctuary.

Lee is a young man who enters a relationship with Christina. He battles severe drug addiction and immaturity, making it impossible for Christina to build a stable life with him despite her initial efforts to help him recover.

Johnathan is an actor who appears to be an ideal match for Christina on paper. Their relationship suffers from fundamental incompatibilities that create anxiety and doubt for Christina leading up to their wedding day.

Katey is a lead actress on the sitcom that makes Christina a star. She serves as a maternal, supportive figure on set, providing the teenage actress with a stable family dynamic she lacks at home.

Ed is a veteran actor who stars alongside Christina. Together with the rest of the cast, he helps create a safe, familial environment on the soundstage that contrasts with Christina's chaotic personal life.

Sadie is the young daughter of Christina and Martyn. She offers her mother a profound sense of purpose and comfort, often resting beside her as Christina manages her chronic illness.

Paul is Bob's father and Christina's paternal grandfather. He maintains a harsh, contentious household and refuses to support his former partner during a period of intense need.

Olive is Paul's wife and Bob's stepmother. She participates in raising Bob but treats him with unkindness, contributing to his difficult childhood.

Lavina is a historical figure connected to the Applegate family. She endures a harsh life marked by illness and addiction after being abandoned by her partner.

Gary is a close friend of Christina who suffers from a terminal illness. His passing marks a somber, reflective moment in Christina's young adulthood.

Scott is a teenage boy who dates Christina during her adolescence. He pressures her into physical intimacy during a family holiday trip, leaving her feeling uncomfortable and upset.