The doc begins in 2014, as the city and the race's organizers prepare for the 118th Boston Marathon, a year after two bombs went off near the finish line. Founded in 1897 (launching the modern, ex-Olympic urban marathon), the marathon is a test of endurance that culminates at the grueling "Heartbreak Hill." The event has been shaken time and again by world events and social change (not least its belated acceptance of women, who'd already run it on the sly), but has always evolved to run another day.
That continuity seemed in jeopardy after the bombing. The Boston Marathon has been a supreme spectator sport as much as a world-class athletic one, and the backpacks that exploded on that Patriots Day were behind the barricades, killing three and injuring hundreds.
Dunham is a marathoner himself and a storyteller, aided by Leonard Feinstein's sharp editing. In deciding to continue its century-old footrace three years ago, Boston faced fundamental questions about human values in a free society challenged by terrorism and fear. Boston, like the city itself, is strong indeed.