Briefly married in 1934, Haigh deserted his wife after serving his first jail term -- for fraud -- in November of that year. Before and during World War II, he chalked up numerous arrests for theft and minor swindles, completing his last prison term in 1943. Appearing to "go straight" at last, Haigh moved into the respectable Onslow Court Hotel, in South Kensington, and rented a nearby basement room for use in perfecting his "inventions." The makeshift lab was stocked with tools, a welding set -- and a 40-gallon vat of sulfuric acid.

On September 9, 1944, Haigh lured a longtime acquaintance, Donald McSwann, to his basement workshop, killing his prey with a hammer, afterward slashing his throat for the purpose of drinking McSwann's blood. The dismembered remains were dissolved in Haigh's acid vat, with the resultant sludge later poured down a manhole. Taking over control of McSwann's nearby pinball arcade, Haigh told the dead man's parents that their son was hiding in Scotland, to avoid military conscription. Once a week he went to Scotland, mailing forged letters to the anxious couple, but their suspicions grew over time, even as Haigh's compulsive gambling devoured his stolen income.

On July 10, 1945, Haigh invited McSwann's parents to his lab, bludgeoned them both, and dissolved their remains in acid. Forged documents enabled him to usurp their estate, including five houses and a small fortune in securities, but gambling, poor investments and a lavish life-style left him strapped for cash again by February 1948.

Haigh's next customers were Archie and Rosalie Henderson, touring his new workshop at Crawley, south of London, when they were shot and slipped into an acid bath on February 12. Haigh later told police of sampling their blood, but he was rational enough to execute the forgeries that netted him $12,000 from the dead couple's estate.

A year later, in February 1949, 69-year-old Olivia Durand-Deacon approached "inventor" Haigh with her scheme for marketing artificial fingernails. Invited to the Crawley lab, she was there shot to death, with Haigh allegedly slitting her throat and quaffing a glass of blood before he consigned her to the acid vat. It took a week to finally dispose of her remains, and Haigh had little to show for his effort, selling off her jewelry for $250 to cover some outstanding debts.

Police responding to a missing person report were suspicious of Haigh's glib answers, his too-helpful attitude, and search warrants were obtained for his basement workshop. Searchers skimmed 28 pounds of human fat from the acid bath, along with bone fragments, dentures, gallstones, and a handbag belonging to Mrs. Durand-Deacon. In custody, Haigh confessed everything, playing up the vampirism angle in his bid for an insanity defense . He confessed two more murders -- of victims called "Mary" and "Max" -- committed solely in the pursuit of fresh blood, but some investigators dismissed the whole story as a theatrical ruse. (Haigh was also observed drinking his own urine in jail.)

Haigh's trial opened on July 18, 1949, with a defense psychiatrist branding him paranoid, describing his acts of vampirism as "pretty certain." Unimpressed, jurors voted him guilty and sane, the court imposing a sentence of death. Haigh was hanged at Wandsworth prison on August 6, 1949.