Never before had she been shut in all night behind closed doors and sealed windows.

Now, as the sense of imprisonment was felt, her body protested; her spirit resented the funereal embrace of security.

It panted for the freedom which gives the challenge to danger and the courage to face it.
She went to the window and opened it slightly at the top, and then sought her bed again; but even as she lay down, something whispered to her mind that it was folly to lock the door and yet leave the window open, if it was but an inch.

With an exclamation of self-reproach, and a vague indignation at something, she got up and closed the window once more.
Again she composed herself to sleep, lying now with her face turned to the window and the door.

She was still sure that she had been the victim of a hallucination which, emerging from her sleep, had invaded the borders of wakefulness, and then had reproduced itself in a waking illusion--an imitation of its original existence.
Resolved to conquer any superstitious feeling, she invoked sleep, and was on its borders once more when she was startled more violently than before.
The Thing had sprung again upon her feet and was crouched there.