At 19, Annie Parker (Samantha Morton) has lost her father unexpectedly as well as her mother and older sister to breast cancer. Although happily married to Paul (Aaron Paul), something just isn't quite right. Filled with trepidation, she visits the doctor and as her world is shattered all over again, Annie decides to fight her cancer diagnosis, refusing to let history repeat itself. Meanwhile, brilliant research scientist Mary-Claire King (Helen Hunt) is on the cusp of proving that some cancers have a genetic link, bringing medicine one step closer to defeating the disease. As both women's lives wind inexorably together, discoveries are made which traverse the realm of science as hope, love and survival become beacons in the darkest days of their toughest battles. Based on an incredible true story, 'Decoding Annie Parker' explores how two women came together to save a life and change the world.