The atomic bomb that destroyed Hiroshima in 1945 exposed survivors, the Hibakusha, to large amounts of radiation. In the years since, they have experienced high levels of cancer, heart disease, and other illnesses. But what about their descendants? Members of the second and third generation of survivors live with the fear that they, too, have been affected. They have taken the government to court, demanding answers. Now, researchers are using the latest technology to unravel a decades-long mystery.