French authorities discovered this plot in 1943 after several of Petiot's accomplices ratted him out. Much to the authorities' dismay, they couldn't find Petiot anywhere. Turns out, he had adopted a new identity, and was now acting as Henri Valeri. As Valeri, he joined the French Forces Of The Interior and quickly moved up the ranks to become captain. One of his main duties? Find Marcel Petiot. He was recognized at a train station and captured several months later. Petiot went on trial in 1946, where he admitted to killing 63 "enemies." The media began calling him Dr. Satan. He was executed by guillotine two months after the trial.