Suranne Jones ("Coronation Street") stars as Dr. Gemma Foster in this mystery-drama series that leads the protagonist down a dark path. Dr. Foster seems to have the perfect life; she is a trusted GP, has many friends and a settled family -- until her husband starts acting suspiciously. The doctor begins to think her husband is having an affair and decides to investigate, but the secrets she uncovers tear her world apart. Gemma's life goes into turmoil as she gets closer to discovering the truth, with her family and patients all suffering as a result of the shocking events that unfold.