An unseen tormentor harasses a reclusive author as a citywide blackout triggers fires, looting and escalating violence during the Summer of Sam in New York in 1977.An unseen tormentor harasses a reclusive author as a citywide blackout triggers fires, looting and escalating violence during the Summer of Sam in New York in 1977.An unseen tormentor harasses a reclusive author as a citywide blackout triggers fires, looting and escalating violence during the Summer of Sam in New York in 1977.