His character's absence was written into the show by having him become a Payload Specialist on the International Space Station.
Diane Farr, pregnant for most of the season, left the show for maternity leave in episode 18 ("Democracy"); her character's absence is explained as a special assignment to the Department of Justice. As this season starts, Colby Granger escapes from jail, and is revealed to be a triple agent. Don and Liz break up halfway through this season, after Liz has trouble with Don's trust issues. J., Megan is conflicted by her work, and turns to Larry for help.
Charlie gets his security clearance back after he and Don fight FBI Security Officer Carl Mc Gowan. The team adds new agent Nikki Betancourt, who arrives shortly after Megan Reeves' departure. Buck Winters (from the episodes, "Spree" and "Two Daughters") breaks out of prison and comes after Don.
Charlie and Amita intensify their relationship, as do Larry and Megan, especially after Megan's kidnapping.
Amita has troubles adjusting in her new role as a Cal Sci professor, and Larry announces his leave of absence—he will be on the International Space Station for six months, which greatly distresses Charlie. Mildred Finch, the newly appointed Chair of the Cal Sci Physics, Mathematics, and Astronomy Division, whom they learn has begun dating Alan.
Meanwhile, Don dates Agent Liz Warner and questions his ethics and self-worth, and receives counseling.
Charlie sees Don's therapist and the two understand one another more.
Toward the end of the season, Don is stabbed, and Charlie blames himself for it.
The aftermath of Don's stabbing causes Charlie to focus more on his FBI consultation work. Notes about Season Five: "Disturbed" marked the 100th episode of Numbers.For example, in the episode "In Plain Sight" (season 2, episode 8), one of the criminals is named Rolle and Charlie's father mentions a meeting with a man named Robert Peterson. The first season run of the show aired between January 23, 2005, and May 13, 2005, at p.m. It sees the start of the working relationship between Los Angeles' FBI field office and Charlie Eppes.Opening: (Voice-over by David Krumholtz) We all use math every day. The main FBI agents are Charlie's brother, Don Eppes, and Terry Lake, as well as David Sinclair.Amita's parents come to visit, which becomes a secondary theme throughout most of the season. Near the end of the season, Don's girlfriend from season 2, Robin Brooks, returns. Charlie attends FBI training camp because he has been working with Don for several years and wants to better understand what his brother does.In the season finale, Megan leaves the team to move back to Washington, D.Noticeable changes from previous seasons include the removal of the opening credit sequence (credits are now done during the first segment of the show), the absence of Peter Mac Nicol's character for much of the season, and the absence of Diane Farr's character for a few episodes.