Petiot promoted himself with typical zeal in Paris, offering patients a wide variety of treatments, claiming credentials both real and imaginary. Advertisements described him as an interne (intern) at one mental hospital where he had actually been an interné (patient). Outside his home-office at 66 Rue Caumartin, Petiot erected a brass plaque so jam-packed with phony endorsements that another physician complained to the medical association and Petiot was forced to remove it.

Bogus credentials aside, Dr. Petiot attracted a huge clientele and built an exemplary reputation. Years later, at the height of his infamy in 1944, police would interview 2,000 patients without hearing a word of criticism about Dr. Petiot.

At the same time, however, rumors persisted that Petiot was an abortionist (illegal in those days) and that he supplied addicts with drugs under the guise of “cures.” In 1934, 30-year-old Raymonde Hanss visited Petiot for treatment of an abscess in her mouth. She was still unconscious when Petiot drove her home after surgery. Hanss never regained consciousness and died several hours later. Her mother, Madame Anna Coquille, demanded an autopsy, which revealed significant levels of morphine in Raymonde’s body. The coroner postponed burial until a full investigation was completed, but authorities closed the case without filing charges. Madame Coquille renewed her complaints in 1942, but the court upheld its original finding of death by natural causes.

Petiot faced his first investigation for narcotics violations in 1935, but police found no conclusive evidence. The next year Petiot was appointed médecin d’etat-civil for the ninth arrondissement of Paris, a post that granted him authority to sign death certificates. As usual, he used the position for personal gain: in December 1942, summoned to pronounce the death of a wealthy lawyer, Petiot was accused of stealing F74,000 from the dead man’s home. Caught shoplifting a book in April 1936, Petiot assaulted a policeman and escaped on foot. He surrendered two days later, tearfully pleading for mercy, citing his military discharge records as proof that he was not responsible for his behavior. Police dropped the assault charge and Petiot was acquitted of theft on grounds of insanity. His wife, Georgette, arranged for Petiot to enter a private sanitorium in August 1936.

Petiot had barely arrived at the hospital when he began pleading for immediate release. His madness had passed, he assured staff psychiatrists. It was a momentary aberration, caused by his preoccupation with a new invention--a suction machine designed to relieve constipation. Dr. Rogues de Fursac found Petiot “chronically unbalanced,” but still recommended his release in early September 1936. Petiot’s liberation was nonetheless stalled while the court appointed three more psychiatrists to review his case. The panel’s report expressed “strong doubts as to [Petiot’s] good faith at any point during this affair,” but the doctors could find no legal grounds for holding him. Petiot was released in February 1937.

Chastened by his latest confinement, Petiot appeared to clean up his act, with the exception of persistent tax fraud. Between 1937 and 1940 he reported less than 10 percent of his actual income. In 1938, for instance, he declared F13,100, while earning closer to F500,000. That year saw him charged with fraud and fined F35,000, despite a spirited defense that included pleas of poverty.

The life of every Frenchman changed in September 1939, when German troops invaded Poland, thus launching World War II. Polish resistance collapsed in October, inaugurating the seven-month “Phony War” between France and Germany. Fighting spread with the Nazi invasion of Denmark and Norway in April. German troops invaded Holland, Belgium and France the following month. The French commander of Paris declared it an “open city” in June 1940, and German troops seized the French capital. A collaborationist French government under Marshal Philippe Pétain was organized two weeks later in Vichy, broadcasting orders for a general cease-fire. Forty thousand French soldiers surrendered on June 22, while the Resistance armed and organized for long years of guerrilla war.

In Paris, Dr. Petiot had a new world of opportunity under German occupation. He would use and emulate the Nazis in pursuit of his greatest and most lethal scheme thus far.