When a band of homeless people cremate a beloved dog in San Francisco's Golden Gate Park, the authorities are willing to overlook a few broken regulations. But three weeks later, when the dog's owner gets the same fiery send-off, the SFPD has a real headache on its hands. The autopsy suggests homicide, but Inspector Kate Martinelli and her partner, Al Hawkin, have little else to go on. They have a homeless victim without a positive ID, a group of witnesses who have little love for the cops, and a possible suspect, known only as Brother Erasmus, who is certainly articulate, but difficult to understand.
Erasmus, Kate learns, is well-acquainted with the park's homeless and with the rarefied atmosphere of Berkeley's Graduate Theological Union, yet he is an enigma to all. He has a genius for blending with his surroundings, yet he stands out wherever he goes. He is by no means crazy—but he is a fool.  Kate begins the frustrating task of interrogating a man who communicates only through quotations. Trying to learn something of his history leads her along a twisting road to a disbanded cult, long-buried secrets, the thirst for spirituality, and the hunger for bloody vengeance.