Peter was a college student, who attempted to mimic Dexter Morgan's style of killing.
Peter was an attractive man in his 20s with mid-length black hair, fashioned like Dexter's but styled to stand up higher. He wore a black T-shirt and black jeans to match it. He had a sinister grin.
Peter's personality was dark. He murdered his father at an early age and, since then, he felt the urge to take more lives. After seeing Dexter on a kill, he copied his style and used it on a female victim. However, Peter did not have any form of code and, soon after, he killed an innocent man. This suggested that he was not only impulsive, but would keep on killing.
Early Cuts Summary
Peter was apparently warped since his childhood, and it led to him murdering his father in a "hunting accident". During college, Peter became the graduate teaching assistant a Dr. Robert Milson. In relation to that, he learned that Milson was a serial killer and watched on as Milson killed many co-eds, but he was never allowed to participate. This caused Peter to grow agitated and hate Milson, yet he still hoped that one day he would have a chance at murder. When Peter secretly watched Dexter Morgan kill Milson, he figured out his own killing style (by copying Dexter's method, minus the dismemberment).
He began to shadow Dexter everywhere, and eventually discovered Dexter's interest in a new kill. Peter beat him to it by kidnapping Jenna Lincoln, strapping her to a table with plastic, and stabbing her in the heart. Peter also successfully lured Dexter to the location so that the "teacher" could watch the pupil in play. Even when Dexter confronted him about this, Peter continued to want to learn everything he could from Dexter...only to be shut out. This caused Peter to act out violently and kill an innocent security guard on campus. This didn't go over well with Dexter.
When set for his final test, Peter arrived at the location. As Dexter tried to take him down, Peter fought back with amazing resilience, but his attempts to take Dexter out failed. He was caught in a trap and rendered unconscious. As Peter watched, Dexter approached him with the very saw he had brought to use on a victim. Dexter then sawed out Peter's neck and buried his body far out in the woods.
Peter's first victim was his father, and it is unknown if he killed anyone else before he met Dr. Milson. After seeing Dexter in action, he took Jenna Lincoln's life and even killed an innocent security guard, to get Dexter's attention.
- Mr. Thornton
- Jenna Lincoln
- Unnamed Security Guard
- Peter is mistakenly called Matthew Thornton in the net article about his father's hunting accident. To further point out, the article repeats the same line twice on the same page, in exactly the same words.
- Chronologically, Peter Thornton is the first Main Antagonist to be killed by Dexter Morgan.