This second book in The World of Shadows has a somewhat slower build than the first book, but that doesn't make it any less compelling. As Arthur and Niccolo search for the Bishop, they must also learn to trust each other. Niccolo soon finds that his naiveté about the world and the evils that lurk may either be his undoing or push him to lengths he never believed possible, while Arthur learns that his resolve to do things differently may not be so easy to accomplish. The story builds in suspense as well as action as our heroes uncover the Bishop's terrifying plans. With a heart-pounding conclusion unveiling a plot that is the stuff nightmares are made of, The Vatican Children is a solid addition to the series and has this reader anxiously awaiting what comes next.
As the World of Shadows is an ongoing story, I highly recommend reading The Everett Exorcism before starting this one. The series is wonderfully written and impossible to put down from the very first page.