The main premise for this title echoes the one for Room, namely that family members must live underground in a basement and pretend it's a normal thing. Instead of a mother and her son, it's parents and their three kids plus a grandma. A couple of other characters come into play later, but mostly story revolves around the youngest son's point of view and how he sees the family dynamic. 
 Things creep along a bit the first half of the book; mostly we learn about the characters and how dysfunctional the family is. At the 50% mark, we finally begin to discover why the family lives in the basement. Things get pretty whacked at this point, but the pace is sped up, and my interest increased in a desire to find out what was going to happen. 
 The ending was not to my liking, and I rolled my eyes and curled my lips more than once. Had the momentum continued, it would have been 3.5 stars.