As an expert and speaker on mass shootings and gun violence, Dr. Lynn Fenton knew it was impossible to "spot a killer." But when she met her new patient, troubled grad student James Holmes, the hair on her arms stood up. She feared he was going to kill. Yet she could find no way to thwart him.

A few months later, Holmes struck: he entered a packed movie theater and opened fire, killing twelve people and wounding seventy; some were left brain damaged, several were paralyzed for life. Immediately the familiar debates reignited: The crisis of mental health access. More restrictive gun laws vs more "good guys with guns." The morality of the death penalty. The legitimacy of the insanity defense.

But what about the victims and bystanders whose lives would never be the same? Dr. Fenton's memoir is a voice for them. Her inability to thwart Holmes's mass murder made her a scapegoat and elicited innumerable death threats. Her chilling account provides an intimate look at her life before and after the Aurora massacre, as well as alarming insight into the sinister patient who called himself "fear incarnate." With unprecedented access to thousands of pages of documents, audio and video recordings, trial transcripts, medical records, and notes, Aurora attempts to answer the question Holmes himself posed in his infamous notebook: "Why? Why? Why?"