Decoding Annie Parker is better as a living-with-disease drama than medical mystery. Veteran cinematographer Steven Bernstein's directorial debut follows the paths of two real-life women who meet only once and briefly. Geneticist Dr. Mary-Claire King (Helen Hunt) is the more famous and, in the film, anyway, less interesting. Her suspicion that some women may have a predisposition to breast cancer made her a crackpot in the '70s, when the film opens, until she was vindicated with the discovery of the BRCA-1 gene in 1990.
Meanwhile, Annie Parker (a luminous Samantha Morton)-- who, as her pool-cleaner/aspiring rocker husband (Aaron Paul) never tires of reminding her, has only a high school education -- spends these long years engaged in her own Erin Brockovich–style D.I.Y. investigation after losing her mother and sister to cancer. Her male doctors tell Annie she's paranoid until her own carcinoma diagnosis arrives.
Famous faces pop in minor roles until it's almost distracting: West Wing veterans Richard Schiff and Bradley Whitford have a couple of scenes, while House of Cards' Cory Stoll wears a terrible hairpiece as a junior doctor sympathetic to Annie's questioning of medical orthodoxy. (Morton's own physical transformations through her periods of health and illness are entirely convincing.) Rashida Jones and Maggie Grace score a few lines each.
The picture's most observant moments track how Annie's recurring cycles of cancer and remission erode her marriage. Her husband blames her obsessive research for the chill before admitting, "I can't look at you" after her mastectomy. Even where the bond of love remains, illness can be a permanent romance-killer, a bitter side-effect Bernstein's half-great, half-just-OK film depicts with compassion and candor.