In Mark Lockwood, George Rabasa has created a sympathetic schlump who finally has a chance to leverage himself out of mediocrity. His writing output consists of books like "How to Talk to Your Teen About [insert topic here]." His marriage is in the doldrums. And his appearance is as slack as his career.

Enter Mercé Casals, aka the Wonder Singer. She's a Maria Callas-like diva, singing as a child to support her family, toppling from the opera world's heights when a precipitous weight loss ruins her voice, taking up with a fabulously wealthy prince and, finally, returning to her insecure, skirt-chasing husband.

Lockwood, charged by their mutual agent to ghost-write Casals' autobiography, has spent hours taping their conversations. He also has developed an infatuation for the comely nurse who attends to the legendary soprano.

And exit Casals. The Señora's death, in the first chapter, forces Lockwood into hiding as he refuses his agent's demand that he hand over his recordings and notes to a big-name writer, a thinly veiled Norman Mailer.

Rabasa, who lives in Minneapolis, has a lot of fun with this book. As his protagonist says of the Señora's recollections: "The material is richest when she gropes for the significant event and brings up instead a small telling moment."

His descriptions are astute and often humorous. Lockwood's rival, Baylor, for example, writes books "packed with gristly prose and squat paragraphs as compact as fire hydrants." And Rabasa aptly captures the tension in a disintegrating couple. As Lockwood's wife pours tea, "her expression says nothing. But as the moment grows he realizes that this nothing is indeed something; her refusal to meet his eyes or respond to his smile is a quiet hostility against the errant partner."

Through it all, the Wonder Singer holds her fans, and readers, in thrall with a tale that incorporates all of life's notes, the high and the low.