Benjaman Kyle was found beaten behind a Burger King in Georgia with no ID and, he said, no memory of who he was. For years he was America's most famous amnesiac — a sweet, slightly rumpled mystery the press loved. This series picks up the story and immediately starts pulling threads.

The filmmakers set out to help. What they get instead is a slow, queasy unraveling, a man who seems to know more than he is letting on, and the growing sense that the documentary they thought they were making is not the one in front of them. The subject turns on them. They keep filming anyway.

It is a true-crime doc about making a true-crime doc, and it works because the filmmakers are honest about how badly they wanted the easy version of this story. The Many Lives of Benjaman Kyle is patient, uncomfortable watch that left me disappointed in the end.