For years, a majority of Americans have continued to support capital punishment – in spite of a determined national campaign against it. I have always believed that Americans are guided by their decency and generosity of spirit – so why do we show this loyalty to such an apparently bloodthirsty policy? I think Professor Robert Blecker has the answer. Americans maintain a deep faith in the old-fashioned idea of fairness. So does Blecker. The first thing that struck me about him was not the ferocity of his arguments, but the intensity of his listening. For every argument he brandished in favor of the death penalty, he invited and awaited my strongest counter-argument. Clearly he was hoping that I would score points against him - help him hone his arguments, even make him a little smarter. I don’t know if I ever helped him – but Daryl Holton certainly did. In Holton, a murderer of children and self-taught legal whiz, Robert Blecker found a worthy adversary. And, stunningly, a friend. Witnessing their extraordinary battle to find the meaning of Holton’s crime, it was instantly obvious that here was a proving ground for Blecker’s most passionately-held beliefs. And a test of both men’s humanity, killer and scholar. Making a film that looks deep inside that friendship was draining, disturbing and, ultimately, exhilarating.