Alice Howland is proud of the life she worked so hard to build. At 50 years old, she’s a cognitive psychology professor at Harvard and a world-renowned expert in linguistics with a successful husband and three grown children. When she becomes increasingly disoriented and forgetful, a tragic diagnosis changes her life --- and her relationship with her family and the world --- forever.

In an ideal world, they would never have met. Vivien Simpson is a happy housewife with a young son. Edward Davis is an ambitious aide to an important Congressman who loves his wife. When an airplane crash brings about the discovery that their supposedly loving and now deceased spouses were involved in a deeply passionate love affair and possessed the same apartment key, they are devastated and baffled by the revelation. Determined to find the answers to their dilemma, they embark on a search for both the reasons for their spouse's infidelity and their place of assignation.