Within a TITLE, Tahlia Jenson discovers a celebrated mythical folklore has withered a distant kingdom and now threatens the culture of her own world.
your hook starts here:
Ten-year-old Tahlia falls asleep wishing to escape the reality of her sickbed, and wakes to find the violet eyes of her doll, Sally, blinking back at her. Magically transported to a land of doll-sized inhabitants, tooth fairies and attack teddy bears, Tahlia learns Sally's playground hides a mystery. Many of the kingdom's children have disappeared, along with the infant princess. When Tahlia realizes she and Sally are next, she may have to give up her childhood innocence--and her lifelong friend--to save not only the dying kingdom, but also herself.
well, I want one of those attack teddy bears for sure.
This isn't specific enough to be compelling. For "you're next" to be scary you have to see who says it. Jaws isn't scary till you know the shark is in the lagoon.