Mary doesn't notice the events going on behind her; she's straining to keep Adam in her sights, her eyes tracking him and the Dark behind him as it billows and strains like an evil genie.

She doesn't notice that she's shivering more than before; she does notice when the strange white mist moves in front of her vision.

And that's almost more frightening than the tornado of the Dark bearing down on them, almost more frightening than the Light going out. Anything could be happening, and she holds on to her apple tree almost tighter than she does to Dickon, feeling the bark scrape her hands, because as long as she's holding it she knows where she is. And knowing where you are is something, at least.