"After a hard school year, V has been sent to her Grandma Jojo's house for the summer in order to get away from it all. But unlike neurodivergent, artistic, sock-collecting V, Jojo is uptight, critical, and obsessed with her spotless house. She doesn't get V at all. V is sure she's doomed to have the worst summer ever. Then V starts hearing noises from inside the walls of the house... Knocks, the sounds of a girl crying, and voices echoing in the night. When V finds a ghostly girl hiding in the walls, they seem to have an immediate connection. This might be V's chance to get back at her perfect grandmother by messing with her just a little bit. But the buried secrets go much deeper -- and are much more dangerous -- than V even suspects. And they threaten to swallow her and her family whole if she can't find a way to uncover the truth of the girl before it's too late." --publisher's website.