Like Damien Thorn and Mark Thorn, Teddy was a member of Bradley Platoon at Davidson Military Academy. His rank insignia in the film shows him holding the rank of cadet corporal. After Sergeant Neff takes over as platoon officer, while Teddy and the platoon are waiting outside his office, Teddy mocks the late Robert Thorn in front of his friends. When Teddy then mocks the Thorn family in front Mark, Mark hits Teddy; causing Teddy to beat Mark up. Damien intervenes and uses his powers to torture Teddy with what appear to be nightmarish visions, until Neff breaks Damien's focus.
Some days later, Damien takes Mark and their academy platoon, including Teddy, on a field trip to a chemical plant. When toxic fumes escape at the plant, Teddy and the other cadets except Damien suffer mild chemical poisoning and are temporarily hospitalized. After Mark is killed by Damien, Teddy attends Mark's funeral.
Teddy openly mocked Mark's family in front of him, then beat Mark up when the latter retaliated. This mutual antagonism ends after Damien subdues Teddy without raising a hand. Afterward, Teddy makes amends with Mark and later is part of the honor guard sent to Mark's funeral by Davidson Military Academy.
When Teddy mocked Damien's late father, Damien warned Teddy not to do so again, which apparently caused Teddy to see Damien as an egomaniac. When Damien returned from meeting with Sergeant Neff, he tortured Teddy with horrific visions for beating up Mark. Afterward, Teddy never antagonized either Thorn again, and the novel mentions he made a point of sitting with them in class.