Ansel is the novel’s antagonist, on death row for murdering four women. Though Ansel abhors being called a serial killer, he fulfills several common tropes associated with the title. As a child, he appears emotionless and kills small animals for fun. He is diagnosed as a psychopath, who puts on a charming façade for the purpose of manipulation. He fancies himself intelligent and is working on a long-winded manifesto about the truth of good and evil, hoping to secure a place in public memory like other murderers before him.

As the narrative progresses, the full story of Ansel’s life unfolds. He was abused as a child and spent his adolescence living alone with no familial connections and no support system. Ansel is obsessed with the idea of alternate universes in which his life might have turned out differently. Kukafka explores this theory through the much more well-adjusted Ellis, who has a similar genetic makeup and early childhood to Ansel but enjoys a loving and stable life after being adopted.

Notes on an Execution puts forth the idea that the label of “psychopath” is used too readily to dehumanize people like Ansel. Ansel knows that he is different from others.