On a sweltering June evening in 1937, American Juliet Stuart Poyntz left her boardinghouse in Manhattan and walked toward Central Park, three short blocks away. She was never seen or heard from again. Seven months passed before a formal missing person's report was made, since Poyntz worked for the Soviet Secret Police and her friends (many of whom were anti-Stalinist radicals in the United States) were scared to alert authorities. Her disappearance coincided with Josef Stalin's purges of his political enemies in the Soviet Union and it was feared that Poyntz was a casualty of Soviet brutality.

In Where Is Juliet Stuart Poyntz?, Denise M. Lynn argues that Poyntz's sudden disappearance was the final straw for many on the American political left, who then abandoned Marxism and began to embrace anti-communism. In the years to follow, the left crafted narratives of her disappearance that became central to the Cold War. While scholars have thoroughly analyzed the influence of the political right in the anti-communism of this era, this captivating and compelling study is unique in exploring the influence of the political left.