In the quaint German town of Fels, Halloween takes a dark turn for eleven-year-old Jo. When her annoying older brother, Hektor, goes missing, Jo suspects he's playing a prank. But then both her father and grandma forget Hektor's name, and his stuff mysteriously disappears from his room.

With the adults of no help whatsoever, Jo starts her own investigation, and uncovers a gruesome legend: A monster lives in the rye fields, and it has been preying on the children of Fels for centuries, ensnaring them into its world under the roots. With two days until the gate between their worlds closes, Jo races against time to save her brother.

Armed with a trusty turnip lantern, and her brother's obnoxious best friend as her only ally, can Jo outsmart the ancient monster, or will the rye fields claim even more innocent victims? Embrace the magic of spooky season and join Jo on a pulse-pounding journey into German folklore where courage, friendship, and darkness collide.