while at the FBI Academy and was at the time fresh from the field in hunting fugitives (with friend Agent Cooper). Liz knows he has mellowed with age and he can hold a commitment with a woman for longer periods of time. He believes that the death penalty is a form of revenge. Don has an ability to understand how criminals think, which causes him to suppress his thoughts in an effort to cope with the horrors that he sees on his job. Don's main weapon of choice is a Glock 19. Evolution over the series Having been Special Agent In Charge of the Albuquerque Office, Don took a demotion in order to obtain a position as Special Agent in the L.A. Field Office, but he did so to be with his family when his mother was diagnosed with cancer two years prior to the series pilot. Margaret Eppes died approximately one year later, and according to the pilot, Don elicited Charlie's help on two cases between her death and the series pilot. These cases involved IRS extortion and stock fraud. Initially uncertain about what Charlie might actually be able to contribute, he reluctantly allows Charlie to assist with their attempts to track down a rapist and is pleasantly surprised when Charlie's math leads to the suspect's apprehension ("Pilot"). His relationship with Charlie was apparently somewhat strained even before their mother's death, as Don is stunned to learn that his little brother has enough security clearance to work with both the CDC and the NSA ("Vector"). He is even more surprised to discover that Charlie doesn't seem to know that his clearance will allow him to walk into the L.A. Office whenever he wishes, rather than obtaining a visitor's pass every time and being restricted in what he can do there. Upon resolving Charlie's status, Don now apparently calls Charlie in on most of his cases. In "Uncertainty Principle", Don loses his temper at Charlie when Charlie once again reverts to working on P vs. NP after Don is shot in the arm by the 'Charm School Boys'. He vents his frustration and anger at Charlie for hiding in his math (members of the fandom refer to this state as 'Numbersville'). In "Vector", Don comforts Charlie when Charlie questions Don heartbrokenly about whether their mother was in pain during those last three months, showing that despite his anger that Charlie