Dr. Roger Buckman is a neurologist and the boss of mild-mannered Dr. Cathleen Dwyer, who worked with him on a study of murderers gaining homicidal rage from lesions located in particular regions of their brains. Kevin Reddick, a serial killer awaiting trial, was one of the duo's test subjects, but he didn't have the lesion, which Reddick realized; the revelation of this would have ended his career.
In turn, Dwyer did have the lesion, so Buckman formed a plan to manipulate Reddick to in turn manipulate Dwyer, seducing her and convincing her to kill a woman in order to cast suspicion away from Reddick. By exonerating Reddick and pinning his crimes on Dwyer, this would have proved Buckman's theory. Buckman's machinations eventually worked on Dwyer, driving her to kill Rosa Dern. When the conspiracy was suspected, Reddick rolled on Buckman, and when Buchman and Dwyer were confronted, they both gave confessions and were arrested. Detective Goren later lamented that Dwyer killed not out of rage, but out of infatuated obsession despite having the lesion, which still debunked Buckman's theory. (CI: "Seizure")