Joy Christianson lives in the sleepy Nebraska town of Ogallala. Last week, Joy went to visit her best friend, Melanie, and instead found her body. She had committed suicide, and now Joy wants to know why (and, really, who can blame her?). Joy has also had to deal with breaking up with Austin, her friend since childhood and boyfriend for the last year. Joy has also lost her faith, although her Down syndrome cousin, Beatrice, tries to remind her about right and wrong in her own innocent way. Now Joy has befriended Raven, one of the bad girls in school, because she wants to distance herself from Melanie and Austin’s friends.First up, I have to say that the opinions expressed in this review are that of the parent, not the Young Adult audience that The Shadowed Onyx is aimed at. I was one of those teens who was hypothetically interested in the spirit world, but who always knew (despite not having a Christian upbringing) that messing with things like Ouija boards was not a good idea. Either they knew fake (and therefore a total waste of time) or they were real, and therefore not something we should be messing around with.As an adult, I can soon see that Joy is suffering from case of survivor's guilt (but to tell you why might spoil the plot). I don't know if a teen would see this underlying issue, or if it would just go over their head. The story is all written in the third person, from Joy's viewpoint. The narrative does seem a bit juvenile, but that could just be the adult me talking.Teenagers are fascinated with the concept of the spirit world, and The Shadowed Onyx is a solid Christian response (although it got uncomfortably close to crossing the line at some points). The author writes with a sense of authority around the spiritual content, while at the same time, she has captured the uncertainty of youth without being moody or melodramatic. The Diamond Estates series is based on her experiences as a resident at Teen Challenge as a teenager, and this experience comes through in the writing.It shows there is power in the language we use. 'Spiritual' sounds so much better than 'satanist', and 'contact' less scary than 'haunt'. But I have two concerns with The Shadowed Onyx. First, parts of the story skate very close to the line, and could almost be seen as a 'how-to' manual. More worrying, a very innocent or undiscerning teenager might not see that this is written from a Christian worldview, and might be encouraged to take the same path as Joy--and for the first half of the novel, Joy's thoughts and actions are quite anti-Christian. And the story is told exclusively from Joy's viewpoint, so there is no indication that she is being lied to and that her actions are wrong."She wasn’t afraid of the dark anymore; in fact, she preferred it. Light was unnecessary because it only revealed half the picture, if that. It crowded out the truth rather than illuminating it."In reading this, it's quite easy to see how a vulnerable teen can be seduced by the power of the dark side, and how well it masquerades as light. As with all the most convincing lies, it is based on the truth. This is a very good novel, and one that many parents of teens would benefit from reading, but it is a story I would recommend to others with caution. Although it is the third book in the series, it is a stand-alone story.Thanks to Barbour Books and NetGalley for providing a free ebook for review.