London, 1934. Doreen Bates is working in the same office as E, an older married man. They strike up a passionate affair, and Doreen records it all in her diary—secret midnight walks, countryside escapades and stolen moments of intimacy. But Doreen longs for a child with E, despite all the taboos of the time. Against the wishes of E, she gets pregnant and is amazed when twins are born during the war. However, Doreen faces an uncertain future—will E ever leave his wife and join his new family? This is the story of a young woman forging her own path in a period of turbulence and uncertainty.