Mary Seacole (Mbatha-Raw) is one of the most influential but now forgotten, heroes of the Crimean War. A devoted nurse, Mary hopes to join the famous Florence Nightingale in the war effort, offering her expertise in tropical diseases and field medicine. However, she is turned away, because of the color of her skin. In desperation, Mary turns to Thomas Day, the handsome, but hapless friend of her late husband for help. She forges her own path to the war front by utilizing his social position as a white man, in combination with her lifetime savings and business savvy. The fearless and flamboyant Seacole sets up shop supplying army men and establishes her own triage unit on the front lines, becoming the first nurse to enter into battle to treat the wounded. SEACOLE tells the story of a remarkable woman who, through her unflinching smarts and boundless altruism, saves the lives of countless men, including a man she learns to love, and changes medicine forever in the process.