Stephen Spaulding used to be a doctor and a family man. Now, two years after his wife and young daughter were killed in an automobile accident, Stephen drives a Checker cab through the streets of St. Louis. He doesn't need the money --- he just does it to relive that horrible day and to tell his imaginary, happier version of the story to the people who use his taxi. When he picks up Dorothea O'Brien, though, she recognizes the falseness of his tale and shocks Stephen into moving past the events of that tragic day.

Dorothea herself is on a quest. Raised by her rich, ultraprotective father in a highly secretive estate (called the Sanctuary) in rural New Mexico, Dorothea has not seen the outside world in nineteen years. Dressed in a long skirt and saddle shoes, Dorothea has never seen television or movies, or even many men besides her own eccentric father and her older brother Jimmy.

Dorothea has come to St. Louis searching for her brother, who seems to have disappeared off the face of the earth. After searching through St. Louis's seedier neighborhoods, Stephen and Dorothea discover Jimmy in a mental hospital. The young man has cut himself severely and is now making wild claims about their mother, who (according to their father) died when the children were young. Dorothea doesn't remember her mother at all, but Jimmy's vivid and troubling recollections of her death send the young woman on an odyssey to discover her past.

Lisa Tucker's third novel is not exactly a mystery, but her brilliant storytelling skills make for a novel rich in suspense. Flowing freely through time and place, told by a half-dozen different narrators, the novel unfolds gradually, revealing a portrait of a family torn apart and of a relationship based on a skewed understanding of love. As the novel moves from past to present, we see the drastically different ways in which two very different men react to sudden tragedy, and we mourn along with the characters as we come to realize the scope of their losses.

ONCE UPON A DAY does find a measure of hope in the end, but not before raising profound questions about the limits of love, the power of the past, and the capacity of the human heart to deal with profound tragedy.