We meet Trudy Elion as a child, and her grandfather is showing her how to fix a broken watch. A few days later Trudy's mother tells her the sad news that her grandfather has been diagnosed with stomach cancer. Trudy's dying grandfather promises her that he will watch over her wherever she goes. Ten years later, Trudy is a bright, vivacious young woman committed to pursuing a career in chemistry, but gender discrimination prevents her from receiving financial aid to graduate school. She gets a job as a lab assistant and becomes engaged to the charming Leonard Canter. Then Leonard is diagnosed with a bacterial infection of the heart's lining and dies. For Trudy this loss is devastating, and she buries herself in her work. Finally, in 1944, Trudy is hired by Burroughs Wellcome as a senior research chemist, one of two women in lab of 75 employees. She is assigned to work with a group of scientists studying how cells produce DNA. Trudy becomes friends with Nick Landon, a kind and outgoing history student. Then Nick reveals Trudy he is suffering from granulocytic leukemia. Trudy realizes she has a new face to put on the disease that has haunted her for years.