Justin Walton, who plays Principal Cosgrove in The Secret of Sarah Pennington, is interviewed about his role in the movie. The Secret of Sarah Pennington is a thriller/suspense film based in a small town called Shallow Grove. Strange events begin to occur around a 20 year high school reunion and a former student who went missing 20 years ago is blamed by most of the town. However, the Shallow Grove police want to blame the events on Jonathan, a visitor passing through as part of a small touring band. Who really did it?