As someone who liked Shea's previous work, this was sort of a letdown. Let's start with the positives: the atmosphere and buildup were done really well. I think this kind of horror, slow and filled with tension, is where Shea's writing shines the most. The way both Winnie and Apollo gradually breakdown, mentally and physically, over the course of the novel due to the stress and torture the box puts them through is the best example of this. Plus, they really know how to paint a gorey picture. Winnie and Apollo themselves were okay. They each had conflicts of their own I liked, but I never really got behind their relationship, as I didn't really feel the chemistry there. It didn't help that the side cast either had no real presence (This felt especially lackluster when considering Winnie's connection to her own family wasn't really given focus til the last five chapters or so. So her suddenly deeply strengthening her relationship to her cousin and brother didn't feel as weighed as it should've been) or were so cartoonishly evil I really didn't take them seriously. Additionally, the POVs of the past Rathbuns felt unnecessary. I do get the generational trauma angle this was going for, but it kind of defeated the mystery behind the box outside of its origins. I think Apollo should have gotten little snippets of their ancestors from the box, or it could have been heavily implied during the duo's searches. The book also just ends on a weird note after the huge nearly-ended-the-world climax. I won't say it outright, but the way Apollo and Winnie come back together after what they just went through felt so anti climatic. All in all, the book was fine. Great atmosphere, but the lack of character refinement and too many povs really bogs it down.