Few incidents in American history have been as meticulously analyzed as the 1969 Manson murders, also known as the Tate-LaBianca murders. And few people know that better than journalist Tom O’Neill, who spent two decades obsessing over the details of Charles Manson and his infamous group of followers known as The Family in hopes of unearthing the true motivations behind the slayings of actress Sharon Tate and others.