London, 1929. Eleanor Hamilton is a dutiful mother, a caring sister and an adoring wife to a celebrated war hero. Her husband, Edward, is a pioneer in the Eugenics movement. The Hamiltons are on the social rise, and it looks as though their future is bright. When Mabel, their young daughter, begins to develop debilitating seizures, they have to face the uncomfortable truth - Mabel has epilepsy: one of the 'undesirable' conditions that Edward campaigns...