The house seemed to sit apart from the others on Katydid Street, silent and alone, like it didn't fit among them. For Violet Hart--whose family is about to move into the house on Katydid Street--very little felt like it fit anymore. Like their old home, suddenly too small since her mother remarried and the new baby arrived. Or Violet's group of friends, which, since they started middle school, isn't enough for Violet's best friend, Paige. Everything seemed to be changing at once. But sometimes, Violet tells herself, change is okay.

That is, until Violet sees her new room. The attic bedroom in their new house is shadowy, creaky, and wrapped in old yellow wallpaper covered with a faded tangle of twisting vines and sickly flowers. And then, after moving in, Violet falls ill--and does not get better. As days turn into weeks without any improvement, her family growing more confused and her friends wondering if she's really sick at all, she finds herself spending more time alone in the room with the yellow wallpaper, the shadows moving in the corners, wrapping themselves around her at night.

And soon, Violet starts to suspect that she might not be alone in the room at all.