It is 1941 and Lil, a young working-class woman from West London, and Margaret, a daring socialite from a well-to-do family, embark on a secret affair. Working side-by-side in a typing pool during the day, at night the two women makelove in toilet cubicles, unlit alleyways, secluded bomb sites, and Margaret's dreary digs when the landlady is out. But when Margaret ends their affair to marry a flight lieutenant, Lil feels she has no choice but to follow suit and marry Alfie Edwards, an old childhood acquaintance.

Alfie goes to war and Lil is left struggling with a heterosexual relationship, two small children, Harry and Maggie, and the loss of her lover, Margaret. Meanwhile, Alfie is taken prisoner of war and sent to a labour camp in Germany. Following the firebombing of Dresden by Allied forces, Alfie is forced to assist with the clean-up operation and is left traumatised for the remainder of his life.

Reunited at the end of the war, Lil and Alfie are forced to build a life together but Alfie can't touch people and Lil can't love people, including her own children. As they grapple with their separate traumas the effects travel beyond them to shape the lives of the generations that follow, to Harry and Maggie, and later, to their grandson, LJ.