He Lured Them with Charm — Then He Dissolved Their Bodies in Acid to Hide Evidence of His Serial Killings

At one point, John Haigh may have thought he could have gotten away with his crimes forever.

The English con artist had seemingly figured out a way to murder without a trace, opening up an opportunity for him to go on one of the country’s most gruesome killing sprees during the 1940s, when Haigh killed at least six people and disintegrated their bodies using sulfuric acid, according to The History Press.

Haigh’s murders earned him the nickname “the acid bath vampire” from local media, and he became known as one of the most notorious killers in English history, according to Cambridge University, where more than 100 of his personal letters – some penned about his crimes – have been housed at the university’s Institute of Criminology since 2007.

The letters proved to be Haigh’s downfall, when police discovered them along with evidence of an acid-burnt body in the back corner of his workshop in Crawley, England. But by that point, for his victims, it was already too late.

A Life of Crime

Haigh struggled in his early adulthood after a life of piano playing and singing gave way to an insurance job that he quickly grew tired of, according to author Neil Root’s book Frenzy!: Heath, Haigh & Christie about high-profile 20th Century serial killers.

The wayward 21-year-old would be fired from his job for stealing cash, launching a life of conning others for financial gain. Haigh was “charming,” according to Root’s book, leading to his success in fraud and forgery.

But soon, Haigh discovered a quicker, more brutal way of getting rich.

The ‘Acid-Bath’ Murders

After he was released from prison in 1944 following a fraud conviction, Haigh first targeted a wealthy former friend, William McSwann, according to Cambridge University. Haigh killed McSwann and disposed of his body using acid before later befriending and killing McSwann’s parents Don and Amy. Haigh would go on to steal the rich couple’s pension checks and take ownership of their properties, selling them for a massive profit — and moving on to his next victims.

According to The History Press, Haigh was never entirely clear about how he made his money, though he claimed to be a civil engineer and inventor. He even had a small workshop in Crawley where he sometimes invited people to discuss business deals, but once inside, the situation took a far more sinister turn.

Haigh would convince his victims to come to his workshop, where the murders and “acid baths” took place. The confident killer believed he had concocted “the perfect murder,” according to Cambridge University. That is, until investigative science caught up to him.

Haigh’s Arrest and Execution

Police grew suspicious of Haigh when a wealthy widow, Olive Durand-Deacon, went missing. Haigh met Durand-Deacon at an expensive London hotel, where he had been living, according to The History Press. Haigh convinced the widow to come to his workshop and see an “invention” he claimed to be working on and wanted her to invest in. But at the hotel, Haigh killed Durand-Deacon and disintegrated her body — this time dumping what was left of the remains in a back corner of the building instead of pouring it down a sewer drain, as he did with his previous victims.

Haigh confessed to the murders after forensic investigators confirmed the sludge found in his workshop contained human remains, according to The History Press. But Haigh would attempt to use insanity as his defense — a claim that’s been debated since a court rejected it in 1949 and sentenced him to death by hanging.

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Professor Friedrich Loesel, a director at Cambridge University’s Institute of Criminology, said there’s “little evidence” that Haigh understood the “emotional impact of what he had done,” leading historians to question whether he exhibited signs of psychopathy. “It is as if he hears the tone but does not understand the music,” Loesel surmised in Cambridge University’s writings about Haigh’s letters.

Haigh was hanged in August 1949, ending what Root called one of the highest-profile murder cases in the post-World War II era — one of several that provided “a level of coverage never seen before, the precursor to the press frenzies which surround serial murder today.”