Heroes of the Zeroes is Nick Rogers’ daily, alphabetical look back at the 365 best films of 2000 to 2009.

Going in, know only this of the story behind 2008’s Dear Zachary: A Letter to a Son About His Father: After the death of his best friend, Andrew Bagby, filmmaker Kurt Kuenne sought to “make one more movie with his friend” and document for Andrew’s as-yet-unborn son, Zachary, the wide web of lives Bagby touched.

Further details will ruin Zachary’s emotionally destructive impact — chronologically recalled by Kuenne in a manner that doesn’t feel dubiously manipulative. However, a few critics have called it that, as well as one-sided.

That’s within their right. But Kuenne’s film wasn’t originally intended for the hearts and minds of anyone who didn’t know Bagby. His narration quivers. He almost abandons the project. Only tragedy gave it wide viewership. If it hurdles past evenhandedness, well, it’s a race against time to preserve as many positive memories as possible.

Zachary is a film about how some bury their faith with their children, people for whom death becomes the only reason to remain alive, surprising overlaps of circles of friends and four consistent words of support that ring out across a continent.

Time Out’s Hank Sartin eloquently argued for Zachary, saying documentaries “should not be judged on their neutrality, but on their persuasiveness and their intellectual honesty about the inevitable emotional manipulations.”

Considering that, Zachary was an unmitigated triumph — a devastating answer to the question of what difference it would make if one person weren’t alive.