Mara whips around. The hall is empty, but the bathroom door at the end now hangs wide open, light off. The footsteps came from there. On the monitor in her hand, the crib view shows Theo asleep and still. So if Theo is in bed, what just ran across the hall?

Mara freezes on the stairs. The footsteps circle the dark hall once, twice, then stop right at the bottom step below her. She can't see anything there. A small cold hand closes around her ankle. A child's voice she doesn't know says, 'Up or down?' She can't answer, and the hand pulls her down into the dark.