I read a lot of true crime books, and thus the religiously motivated murders of Brenda and Erica Lafferty were of interest.What I did not expect from this book was a detailed and interesting look at the history of the Church of Jesus Christ of Latter-Day Saints (Mormons) and how the Fundamentalist LDS movement splintered away from the main body of the church.I think most of us are familiar with FLDS due to the arrest and prosecution of Warren Jeffs for polygamy, statutory rape, etc. What I suspect most of us do *not* know is how the FLDS motivated the murders of a young woman and her infant daughter.Brenda Lafferty was trying to help her sister-in-law escape from an abusive marriage. One of the murderers, Ron Lafferty, was the abuser in question -- and when his wife left him, he believed that God had given him a revelation to kill Brenda (and her infant) for causing his wife to disobey. (FLDS women are expected to be 100 percent submissive to their husbands' will, without question.)The history of the church and its views on polygamy also played into this book as the Lafferty brothers had embraced the premise themselves.This is a clear-cut examination of religious mania, in my opinion. I think that most rational people do not believe that a deity addresses them -- especially not in terms that a particular person must be killed. The psychiatric examinations of the Laffertys are also discussed in detail.Well worth reading for those with an interest in the subject matter.