This episode is about an audacious experiment conducted at the end of the second world war by one of the most remarkable figures in twentieth century science. What happens to people when, for months on end, you deny them food? The best record we have of what exactly happened in ansel key's laboratory is in a box of taped interviews stored away in the archives of the library of congress. Each tape runs roughly two hours in length. They contain the recollections of 18 of his subjects, who sat down in their eighties to leave a permanent record of their experience.