Emma killing her child
LaValle describes Emma brutally torturing and ultimately killing her child with vicious and cruel imagery. Initially, this imagery is used to underscore Emma's depravity. But as readers learn more, this imagery is used to show the dangerous threat the changeling (and other supernatural forces) pose.
The island
LaValle describes the island's dense forests, dark and looming trees, and the overwhelming feeling of being enveloped by nature with tremendous detail. Ultimately, the forest is a place where Apollo's fears lie.
The asylum
LaValle paints a picture of an abandoned asylum, with its haunting hallways, peeling paint, and decay and desolation. This imagery mirrors the horrible way society treats those suffering from mental illness and the precarious environment in which Apollo and other characters find themselves.
Books
Towards the start of the novel, there is frequent imagery surrounding books. Many of the books, which invariably appear in Apollo's dreams, have the word "IMPROBABILIA" stamped on them. These books not only reflect Apollo's precarious state of mind, but they foreshadow his eventual quest to find the truth from his wife.