escapes from jail and is revealed to be a triple agent. He then rejoins the team. Don and Liz break up halfway through this season after Liz has trouble with Don's trust issues. Amita's parents come to visit, which becomes a secondary theme throughout most of the season. Due to her work at the DOJ, Megan is conflicted by her work and turns to Larry. Near the end of the season, Don's girlfriend from season two, Robin Brooks, returns. Don and Robin then continue their relationship. Charlie attends FBI training camp because he has been working with Don for several years and wants to understand better what his brother does. In the season finale, Megan leaves the team to move back to Washington, DC, and Charlie goes head-to-head with Don about a case. This causes Charlie to send information to scientists in Pakistan. He is subsequently arrested and has his security clearance revoked to no longer help Don on cases. At the end of the episode, Don drives away to another case, and Charlie admits that giving up FBI work will be more challenging than he expected. Several characters from previous seasons did not appear in season four, most notably Mildred Finch and Ian Edgerton. Season 5 (2008–09) The fifth season premiered on October 3, 2008, and the season finale aired on May 15, 2009. The season premiere was moved back one week to accommodate the 2008 presidential debates. Season five opens three weeks after "When Worlds Collide" (season four's finale), with the government dropping the charges against Charlie. Charlie gets his security clearance back after Don and he fight FBI Security Officer Carl McGowan. Don begins to explore Judaism. The team adds new agent Nikki Betancourt, who arrives shortly after Megan Reeves' departure. Robin is offered a promotion but turns it down. Buck Winters (from the episodes "Spree" and "Two Daughters") breaks out of prison and comes after Don. Alan suddenly finds himself coaching CalSci's basketball team. David becomes Don's primary relief supervisor. DARPA tries to recruit Charlie, but he turns down their offer. 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. Amita is kidnapped, and the team races to find her. After she is rescued, Charlie proposes to Amita. Her response is left undisclosed. "Disturbed" marked