It’s 1976 and Boston is a city on the brink.

Two years after a court order desegregating the city’s public schools, racial tensions have reached a boiling point.

The city’s mayor is walking a tightrope to maintain his reputation as a racial healer while his populist rival sees her opportunity.

His young aide, Patrick Mulraney, is struggling to hide what he does for a living from his anti-busing activist parents.

And as the city fills with smoke and flame, Patrick’s younger sister Meredith and Tristan Stone, one of the students bused into South Boston high school, are looking through it all and meeting each other’s eyes.