“What they did remember—and in the nightmares that bridged the weeks and months that followed, this was no better—were the faces that populated the billious light of the train windows on the other side of the tracks, where the final double-decker carriages in the train’s long chain had finally jerked to a stop. Those who occupied those cars would recount similar relationships with those who stood on the platform. Together they played out an improvised duet on the emergence of human horror.”