Twenty-One doesn’t go past Kenner Street. Sure, on the map the route appears to circle the block at Eighty-Second, but in fact it just stops a couple blocks away.

Not that there’s anyone in its seats by then to object.

It used to be the “bad part of town” was shorthand for the presence of poor or, specifically, black people. The idea seems quaint today. Twenty-One is a predator bus, no trifling machine: it disappears trucks and once ate a pack of thrashers. But each time it hauls up short at Eightieth, rattles, and executes a difficult turnabout.