Some days Nora Nolan thinks that she and her husband, Charlie, lead a charmed life—except when there’s a crisis at work, a leak in the roof at home, or a problem with their twins at college. And why not? New York City was once Nora’s dream destination, and her clannish dead-end block has become a safe harbor, a tranquil village amid the urban craziness. The owners watch one another’s children grow up. They use the same handyman. They trade gossip and gripes, and they maneuver for the ultimate status symbol: a spot in the block’s small parking lot.

Then one morning, Nora returns from her run to discover that a terrible incident has shaken the neighborhood, and the enviable dead-end block turns into a potent symbol of a divided city. The fault lines begin to open: on the block, at Nora’s job, and especially in her marriage.