The compelling true story of the three women — a Manhattan psychiatrist, a glamorous magazine writer, and a troubled young woman — behind the psychology case that shook the world.

In the 1950s, Sybil Dorsett, a woman from a tiny Midwest town, was diagnosed with a new psychiatric condition — multiple personality disorder. Sybil was believed to have 16 separate personalities living within her: from aspiring carpenter Mike to intensely religious Nancy; from impertinent schoolgirls Peggy Lou and Peggy Ann to depressed grandmother Mary; from whimpering toddler Ruthie to the bookish, highly critical Clara.

When Flora Rheta Schreiber wrote about the case in her 1973 book Sybil, it immediately became a bestseller. Soon the Sybil case was a pop-culture phenomenon, and it grew to near-mythic proportions. The case became a touchstone for issues surrounding identity and sexuality, influencing the way millions of people saw their bodies, relationships, and psyches. And it gave rise to a new wave of diagnoses: before Sybil, there had been fewer than 200 known cases of multiple personality disorder in history; afterwards, approximately 40,000 people were diagnosed in just a few years.

In this groundbreaking book, journalist Debbie Nathan reveals, for the first time, that the Sybil case was an elaborate fraud — albeit one that the perpetrators may have half-believed. Nathan follows an enormous trail of papers, records, photos, and tapes to show that what really powered the legend was a trio of women who together spun their story into bestseller gold. The result is an intensely fascinating portrait of a pop-culture phenomenon and the complex psychological factors that primed the world to receive it.