His taste for blood surfaced early in life, when Pleil tortured and killed a cat at age seven. Later, as a teenage soldier during World War II, he had an opportunity to witness victims stripped and starved to death by the Gestapo, recalling the grisly spectacle as "my finest sexual experience."

In March 1946, Pleil claimed his first human victim, braining Eva Miehe with an ax and dumping her body in a canal. Others would follow, through 1946 and early 1947, with Pleil impersonating a policeman, offering to escort female refugees across the frontier from East Germany into the western zone. Instead of sanctuary, they found death, invariably raped by Pleil, then killed and mutilated as he tried his hand with hatchets, hammers, knives and stones. In 1947, he was charged with manslaughter and sentenced to twelve years in prison after impulsively axing a salesman to death. Marking time in his cell, he prepared a diary titled Mein Kampf: signing it "by Rudolf Pleil, death dealer (retired)."

The killer's hopes for freedom were demolished when a lone survivor of his murder spree, Frau Lydia Schmidt, identified Pleil as the man who bludgeoned her and then did "indescribable things" to her prostrate body. Police launched a full-scale investigation, ultimately charging Pleil with nine rape-slayings. Five of the victims were never identified, but detectives did name two accomplices. At his trial in Brunswick, in November 1950, Pleil would share the dock with 36-year-old Karl Hoffman, charged in six slayings, and 22-year-old Konrad Schuessler, linked with two murders and one bungled attempt.

Pleil's behavior was bizarre and arrogant throughout the trial. Whenever prosecutors made a reference to his estimated body count, he interrupted them indignantly. "It is 25," he insisted. "I had 25 victims but they can find only nine bodies. You underrate me. I am Germany's greatest killer. I put others, both here and abroad, to shame."

Pleil angrily denied that any of his victims had been killed for purposes of robbery, maintaining that the random slaughter had been "necessary for my sexual satisfaction." "What I did is not such a great harm," he declared, "with all these surplus women nowadays. Anyway, I had a good time."

Convicted across the board, all three defendants were sentenced to life imprisonment. Pleil passed his time by writing to authorities and offering the whereabouts of new remains, in exchange for an "airing" to visit the scene of his crimes. On one occasion, he wrote to the mayor of a town, offering his services as a hangman; his credentials for the job could be determined by examining an old well on the city's outskirts - where authorities retrieved a woman's strangled corpse.

In time, Pleil tired of the sadistic game and made good on his promise that "I'll hang myself one day." In February 1958, a jailer found him dangling in his cell, the final victim of his own desire to kill.