Dorothea Fenchurch has reached late middle age and feels restless and invisible.
She wants to have crisis talks with her husband Julian to decide what to do about their flagging marriage but events seem to get in the way of every opportunity.
When a burglar alarm goes off in the middle of the night she encounters Norman, a security guard, who influences her to be more daring in her one wild and precious life. She finds herself responding with outrage to incidents in the neighbourhood and becomes angry at the unfairness of society. Her life has been privileged. Julian, though neglectful, has kept her in a comfortable style for which she is grateful and she feels guilty for not appreciating him.
But perhaps Dorrie has been too comfortable. Emotionally she feels starved especially since her beloved only son Paul left home. She starts to take risks and a transformation begins.