When both men are found guilty and sentenced to death, Capote almost recklessly intercedes on their behalf to find them better lawyers. They didn't get sufficient representation, he reasons, managing to help draw out the legal process. But, as the film makes perfectly clear, Capote has ulterior motives for his early involvement in their case. After all, he needs them to stay alive long enough for him to get the full story of the case.
Through his repeated visits in Smith's jail cell, Capote begins to understand what makes the young criminal tick. In doing so, he realizes that he and Smith aren't too different. Both came from broken homes with neglectful mothers, and Capote soon feels empathy for how Smith's life has turned out. "It's as if Perry and I grew up in the same house. And one day he went out the back door and I went out the front," he tells Lee.
Of course, even as he learns more about Smith, he grows frustrated at the man's unwillingness to share with him what happened that fateful night in 1959. Gaining confidence from Capote's involvement in the case, the two criminals begin a long appeal process that is a form of torture for the author. Without their execution, he has no end to his book.
Always a regular social drinker, Capote begins drinking more, falling into a deep depression over his inability to finish his book. In the process, he keeps Smith at bay by claiming he's not even come up with its name, let alone made any real progress in writing it. The scenes between Hoffman and Collins (who gives a very effective performance of his own) are pretty riveting stuff, with each character seemingly opening up his heart, even as both hold back pertinent information from each other.
Obviously, Capote eventually got his ending and finished his book. But the experience, which included being a witness to the execution, left him a shell of his former self. At the end of his five and a half year journey to create a great literary work, it would seem that the Clutters weren't the only victims.
In his desire to craft a masterful piece of non-fiction, Capote (who never took notes during his interviews, claiming to have a 94 percent retention rate) disregarded an important and generally followed rule of journalism: don't get too close.
(Rated R for some violent images and brief strong language.)