Here's the summary from Goodreads: With the clock ticking until the virus takes its toll, Rhine is desperate for answers. After enduring Vaughn’s worst, Rhine finds an unlikely ally in his brother, an eccentric inventor named Reed. She takes refuge in his dilapidated house, though the people she left behind refuse to stay in the past. While Gabriel haunts Rhine’s memories, Cecily is determined to be at Rhine’s side, even if Linden’s feelings are still caught between them. Meanwhile, Rowan’s growing involvement in an underground resistance compels Rhine to reach him before he does something that cannot be undone. But what she discovers along the way has alarming implications for her future—and about the past her parents never had the chance to explain.
What I Liked: 1) Reed. Reed was a great addition to this series. It's about time we met someone from First Generation that was an actual parental figure for Rhine, Cecily, and Linden. I finally got a chance to see that not everyone from the First Generation was not just worried about finding a cure, but worried about the quality of life for them while they were living. He was gruff but likeable, and his interactions with the main characters really allowed them to let someone take care of them. 2) Cecily. I really enjoyed getting to know Cecily better in this book. She seems to have grown up a lot in Sever, both as a person, and as a mom. She gets a lot stronger in her character, and she finally became someone I really liked. 3) The emotions. Sever really drug me over the coals, emotionally. I don't want to give anything away, but there are so many times when I was just breathless with anticipation. I think you'll be surprised at some of the events that happen, but pleased with the overall outcome. 4) The ending. Sometimes I'll finish a series and be somewhat pleased with the outcome, but wish parts of it had ended differently. That was not the case with this one. Despite the fact that some things happen that just break your heart, I was excited to see that Rhine's ending was going to be a happy one. All of the questions (and there are some huge ones in this series) that started way back in Wither, finally come to a satisfying conclusion.
What I Didn't Like: Loved it. This series is one I will enjoy over and over again.
Overall Thoughts: Sever was a captivating conclusion to a unique and intriguing series. The character growth that began in Wither continues throughout the series, endearing each of the main characters, and several of the supporting characters to the reader. The plot flows with uninterrupted ease, and the overlapping story arcs never compete for top billing. If you haven't had the chance to start this series, I highly recommend it. If you've started it, know that Sever was worth the wait.