Subtitle from cover.

As the Chief of Rheumatology at Columbia Presbyterian, Dr. Paul Allen's specialty is diagnosing patients with conflicting symptoms, patients other doctors have given up on. He lives a contented life in Westport with his second wife and their twin sons--a life hard won after a failed marriage earlier in his career that produced a son named Daniel. In the gripping opening scene of this propulsive novel, Dr. Allen is home with his family when a televised news report announces that the Democratic candidate for president has been shot at a rally. Daniel is accused of pulling the trigger. Overwhelmed by a vortex of feelings -- guilt, anger, incredulity, love -- Allen immediately sets out to find the truth, applying his diagnostic skills to the mystery of his own son.