She tried to keep the baby up late but it fell asleep in her arms. She carried it into the nursery and put it in the crib. She closed the door and tiptoed out.

She turned on the baby monitor.

For hours there was nothing, just the baby’s steady breathing. She watched TV with the sound turned down to a murmur, watched talk-show hosts teasing their willing celebrity guests. It was visual white noise that kept her from thinking straight. What would she do? Was she one of those people who would start hearing voices—voices that would tell her to kill her baby? How would she know which voices to trust?

After midnight the noises started again. At first they were just ripples in the static. Then the baby’s breathing became labored and there were sounds like electronic coughs. She listened so hard that she became sure she was creating patterns in the noise where there were none. And then she heard it distinctly: creaking. As if the baby were sitting up.

There was a hitch in the baby’s breathing, as if it were struggling, and then another creak, and then a light thump, as if it had landed on the floor. Then, little steps. Her scalp prickled. She felt a cold shiver of adrenaline. Then the baby cried, a plaintive, questioning cry.

The sounds were obscured by a burst of static. And then the baby’s breathing grew louder, closer. As if it had picked up the base and was examining it.

When the cry came again she pulled her feet up on the couch, a stupid, instinctive retreat, pathetic, as if the baby were a rat on the floor. The footsteps grew louder, as if the baby were pacing the floor, confused. Or angry.

She stood. She willed herself to take deep, slow breaths. Maybe she was a bad mother, maybe she was going crazy, but she was not going to be afraid of her own baby.

She turned on lights until the living room blazed bright as day. She turned on the lights as she went down the hall. Quickly, before she had time to become afraid again, she turned the handle and pushed the door open.

Light slanted into the nursery, illuminating the fuzzy white sheepskin rug in the middle of the room. The baby wasn’t standing there. But the baby wasn’t in the crib, either.

It took her a moment to realize that the baby was right in front of her, climbing the bookcase, looking at her over its shoulder, the light from the hall flashing red in its eyes. Like an animal.

Keir Graff’s most recent novel is My Fellow Americans. He is the senior editor of Booklist Online, where he writes Likely Stories, a blog about books and book reviewing.