Knight’s second installment in the Finn & Botts chapter book series will appeal to younger readers seeking a mystery studded with fossil facts. Anthropomorphic pig best friends Finn and Botts are excited to spend the night at the local natural history museum, accompanying their class on a charity sleepover to raise funds for the new dinosaur exhibit. After they realize missing dinosaur bones might be tied to a more nefarious scheme, however, they must break the rules in order to crack the case and save a place they both love. Most of the secondary characters would benefit from more development, including the McKinnsey twins, Manny and Danny, unruly classmates who get in the way of Finn and Botts’s aspiring detective work, but readers will root for the intrepid protagonists until the final page. Dynamic grayscale illustrations interspersed throughout additionally help readers visualize the case while underlining the strong bond of friendship between the titular characters. Though some plot points feel convoluted, the author’s seamless inclusion of dinosaur facts and a back matter puzzle worksheet make this an interactive, educational adventure. Ages 8–up. (Self-published)