The staircase in the fireplace

When Sophie and Claire were in the old estate of their grandmother, they expected anything, but not that. In one of the fireplaces, the girls found a staircase that brought them ... to the magical world! But this world turned out to be unfriendly - a terrible ghost immediately attacked the sisters, from which they barely managed to escape. A timid Claire hoped to never climb the stairs in the fireplace and not see that strange place. But when Sophie disappeared one night, Claire had no way out. And now she must find her sister in an amazing, but cruel world where people know how to work miracles, but do not trust each other, and where beautiful unicorns used to live, but now they live only in old legends. Can Claire gain strength and courage to find and save his sister, or lose Sophie ... again?