Rolling Stone magazine published a story in November 2014 describing in chilling detail a student's account of being brutally raped by seven men at the University of Virginia. Several days later the magazine's editors received an email from the reporter with the subject line "our worst nightmare." "We're going to have to run a retraction," wrote Sabrina Rubin Erdely about her now-discredited story, "A Rape on Campus." The message is among hundreds of pages of notes...