Married for almost 50 years, Grant's (Gordon Pinsent) and Fiona's (Julie Christie) commitment to each other appears unwavering. Their daily life is filled with tenderness and humor; yet this serenity is broken by Fiona's increasingly evident memory loss - and her restrained references to a past betrayal. For a while, the couple is able to casually dismiss these unwelcome changes. But when neither Fiona nor her husband can deny any longer that she is being consumed by Alzheimer's disease, the couple is forced to wrenchingly redefine the limits of their love and loyalty - and face the complex, inevitable transition from lovers to strangers.