The Shadows (Books of Eleswhere, Bk. 1)

When eleven-year-old Olive moves into a crumbling Victorian mansion with her parents, she knows there's something strange about the house - especially the odd antique paintings covering the walls. And when she puts on a pair of old spectacles, she discovers the strangest thing yet: She can travel inside the paintings, to a spooky world that's full of dark shadows. Add to that three talking cats, who live in the house and seem to be keeping secrets of their own, and Olive soon finds herself confronting a dark and dangerous power that wants to get rid of her by any means necessary. It's up to Olive to save the house from the dark shadows, before the lights go out for good.