Remember, never dig into unsolved mysteries. You never know the price people paid to bury them. Beneath the surface of false tranquility, most truths are cruel. To put it simply, if you see a book on the ground on your way home from work, don't touch it. Unfortunately, Zhou Yan didn't realize this at first, so he picked up the book. The book has an awkward name—A Detective's Training Manual. As for the author...his name is Feigua.