Jason Segel is an actor, a writer, and an author. Segel wrote and starred in Forgetting Sarah Marshall and co-wrote Disney's The Muppets, which won an Academy Award for Best Original Song.

On television, Segel starred on How I Met Your Mother and Freaks and Geeks. He is the co-author of the New York Times bestselling series Nightmares! Otherworld is his first novel for young adults.

Kirsten Miller grew up in a small town in the mountains of North Carolina. At seventeen, she hit the road and moved to New York City, where she lives to this day.

She is the author of two other Kiki Strike books, as well as the bestselling The Eternal Ones and All You Desire.