Friends of Harper Lee knew to heed certain unspoken rules. Most sensed that it was best not to ask her what she was working on. They also learned not to express concern over her excessive drinking, or to indulge the prying questions of yet another meddlesome biographer. Most of all, nearly everyone—from her closest relatives to her Upper East Side neighbors in New York—understood that they should never, ever, bring up “To Kill a Mockingbird.” Lee's acclaimed 1960 novel may have brought her fame, fortune and millions of readers, but it had also become a millstone. In 1962, upon the release of the Oscar-winning film adaptation, Lee told a reporter in her native Alabama that she wanted to disappear. After giving one last interview two years later, she largely receded from view until her death in 2016, at the age of 89, in an assisted-living facility a few streets from where she grew up.