When Peter Gentry and his family move to a new town, Peter isn't thrilled to enroll in a private school that is Shaping Minds and Saving Souls. He is even more disappointed when his fourth grade teacher, Mrs. Anderson, turns out to be downright evil. When she met his mom, she seemed sweet, but Peter quickly realizes its just a mask she wears for parents.

Brady Heath is a new kid, too, so he and Peter become fast friends out of necessity. They soon learn that Mrs. Anderson is just the tip of the iceberg of bad stuff at St. Thomas Christian Academy. In order to be accepted at their new school, among their peers and the faculty, Peter and Brady must spend one endless night locked in the scary old place.

With the lights turned off, St. Thomas is a very spooky placeand things only get spookier as more time passes. Will Peter and Brady survive the shadows and secrets hidden in the dark, and what will be Peters testimony? In the spirit of Goonies and Stranger Things, Testimony challenges young Peter to rely on friendship and possibly put his trust in a higher power.