Don is an FBI agent and Charlie is a mathematics professor who consults with Don's team.
Eventually, they realize Ian's intentions and work to have him released from prison.
He is the FBI's best sniper, as well as being the fourth best shot in the United States.
He is also a top tracker, and has the luxury of choosing his own cases.
This article contains character information for the television show NUMB3RS.
The focus of the show is the relationship between brothers Don and Charlie Eppes.