Rose Mackenberg started as a believer: In the early 20th century, the American public seemed to be in a state of continuous mourning. In just a few years, World War I and the Great Flu of 1918 had claimed nearly 800,000 American lives. The environment of grief provided a fertile ground for the movement known as Spiritualism, and its practitioners gained huge followings by claiming they could communicate with the dead.
In the early 1920s, Brooklyn-born Mackenberg was working at a detective agency in New York when she was assigned a case about a psychic who had recommended worthless stock to a local banker. A mutual friend introduced her to magician Harry Houdini, who was then waging his own crusade against Spiritualists. At the peak of his career, Houdini had decided to use his spotlight to denounce a practice he just couldn’t stomach: psychics who preyed on the bereaved. He’d recently announced a $10,000 reward to any medium who performed a feat he could not replicate with various well-known tricks.
Impressed by Mackenberg’s detective skills, he offered her a job as an investigator helping him unmask Spiritualist con artists. She hesitated: Personally, she believed communication with the world beyond was possible. This job, Houdini replied, would be a great way to test that.
Houdini himself had sought solace in Spiritualism after losing his beloved mother, Cecelia Weisz, a decade earlier. In one seance he listened as the medium relayed a long and dramatic letter allegedly written by his mother—in English, a language she never spoke.
When Houdini was just starting out as a performer, he and his wife Bess had included a medium act in their stage show. But he had grown disillusioned by seeing how it affected those in mourning with false hope. His disillusionment turned to anger; then his spiritual yearning turned into a kind of crusade for justice. But few Spiritualists would let themselves be confronted by him—Houdini was simply too famous—both as a magician and “spook-baiter,” as Mackenberg once called him. By the time he hired Mackenberg, she joined a staff of around 20 investigators. She quickly became the most renowned among them.
Here’s how it worked: Mackenberg traveled ahead of Houdini’s tour, scouting local mediums and con artists for the magician to later unmask on stage. She lingered at department stores and read through the local papers to suss out the town’s psychic-types. She then selected a new identity and ventured into their seance rooms.