Anne Cassidy's "Dead Time" was a captivating read for me, for the most part. I have a love for mystery/suspense/thriller novels, and I don't see that many of them often in the YA genre. The story commences with a protagonist named Rose, who lives with her grandmother - five years after her mother and stepfather disappear without a trace. She has a stepbrother named Joshua, who is like her in more ways than one, but the two haven't seen each other for quite some time.The day that she's supposed to meet with Joshua again for the first time in a long while, she encounters a classmate/former bully who's subsequently murdered, and she's the key witness of it. This sends the first shockwave around her school, peers, and community. Yet, the chain of tragedy doesn't end when another murder occurs, and Rose is put firmly in the crosshairs of suspicion. She has to put together the pieces of three major cases in the novel - who murdered the two students, and where are her mother and stepfather? Are they truly dead or is there something more behind their disappearances?I really liked the way this novel unfolded for the first 2/3rds of the story. I did think it could've given more expansion as to why certain plot threads and scenarios were what they were, but it kept me reading to see how Rose would fare in the mix of the mysteries she took on. Rose can be seen as quite cold and brash, but I liked that she wasn't a perfect heroine. While she had her flaws, she did come to terms with a least a few of her mistakes in certain turns of the story. I also liked seeing her relationship with Joshua, though it had its moments of tension considering the search for their parents.The last third of the novel, however, it unraveled at the seams. That's not something one should have happen in a mystery novel when you spend so much time building up the players, investigative elements and relationships. The first murder reveal seemed very plausible, if a bit haphazard in its resolution, but the second left a plot door wide open. I think it leaves way for another novel in what seems to be an ongoing series. Yet, the plot thread felt a bit tacked on. I was disappointed with it. Also, while I liked there was a close relationship between Josh and Rose in the beginning, I wasn't sure if I completely felt convinced by how their relationship turned in the latter part of the novel. The assertions by Rose made me feel that it was more told than shown, more forced than natural. It didn't help that Rose's rash nature made it seem like she was more likely to push away from her relationships than embrace them. I didn't like how the two threads that are left open at the end came across. It didn't seem right that the person responsible for one of the murders could just be "off-the-hook" in that way, still be connected to Rose, and the reveal about the parents didn't seem all that jarring for the build-up that it had. I'm torn between whether I should read the next book in the series, but considering it was an interesting novel when it hit the ground running, I might see what else this author has in store for Rose.Overall score: 2.5/5Note: I received this as an ARC from NetGalley, from the publisher Bloomsbury Children's Books/Walker Books for Young Readers.