Annie is not the first love of Graham's life but she is, he thinks, his last and greatest. Very recently, he has faltered; but he means to put it right.
Here they are in marriage, in late middle age, in comfort. Mismatched, and yet so well matched: the bookseller with his appetite, his conviviality, his bigness; the photographer with her delicacy, her astuteness, her reserve. The children are offstage, grown up and scattered on either coast; Graham's first wife, Frieda, is peaceably in their lives, but not between them.
Then the unthinkable happens. Now Annie stumbles in the dark: did she know all there was to know about the man who loved her? If no marriage is without its small indiscretions, how great does a betrayal have to be to be to break it?