James Aloysius Piper, mostly known as Peter, is relentless when pursuing a story for his newspaper, the Herald. So when a woman's body is found burned beyond recognition in the marsh near El Cerrito, he is even more eager than the local authorities to uncover her identity and find out what happened to her. Helping to solve the case is clinical psychologist Dr. Cavanaugh, who uses cutting-edge forensic techniques to glean crucial information from a few strands of the woman's hair that escaped the flames.

After Cavanaugh's discoveries tie the corpse to Sheila O'Shay, the missing wife of millionaire Don Ellsworth, it's up to Peter Piper to use all of his craft and charm as a reporter to coax out any secrets the couple may have been hiding.

The Tule Marsh Murder was inspired by a real case that had captivated the San Francisco Bay Area public a few years earlier, and Dr. Cavanaugh is based on the pioneering forensic criminalist Edward Oscar Heinrich who became known as "America's Sherlock Holmes." Though Nancy Barr Mavity may not be remembered as vividly as her contemporaries, such as Mary Roberts Rinehart and Ellery Queen, her mystery novels were groundbreaking in their use of science in the detection of crime, with psychology and forensics frequently providing key clues to the solutions.