The best one can say about this film is that it expands the territory covered by the other two. Capote (2005) was more about the writer than the criminals, whereas In Cold Blood (1967) was more or less a straight thriller about the crime and the people involved. This film squeezes out some extra mileage by giving a portrait richer in detail about the fascinating personality of the author, though Toby Jones' portrayal lacks the texture and depth of Hoffman, though more finely etched. The treatment of the criminals' personalities is heavy handed, unnecessarily stretched, and maudlin. Keeping the other two films in mind, much of this is definitely redundant. The 2005 film was sufficient, and the other two seem just for curiosity's sake. The three movies in their totality are informative about how this particular best seller got written, and the pain, effort and sacrifice behind a creative triumph. Capote wrote little after this. Nor did his friend, Harper Lee, write a second novel after the one which got her the Presidential Medal.
Nothing like bloodshed to sustain interest over a span of three films.