Meghan Doyle

Meghan Doyle said she took the position at NTAC as she felt that is where she could "do some good". Although she is initially dismissed by Agent Garrity to be a purely political appointment, she shows her abilities by giving Tom Baldwin classified information on Isabelle Tyler as a means to discover the whereabouts of Alana Mareva . She knows that this is an illegal act, but is fully aware that her primary mission is to bring in Jordan Collier; and that, should she fail, "no amount of toeing the line" will protect her.

Meghan quickly shows her interest in the cases of the 4400's themselves, specifically Shawn Farrell's healing ability; it is then revealed that her father is suffering from pneumonia and Huntington's disease and is not expected to live much longer. She leans on Tom for support, revealing that DC have forbidden her to ask Shawn to heal her father using his 4400 ability; as the head of NTAC she is supposed to "set an example" and not gain from the use of these now-illegal abilities. After DC is forced to back down by public reaction when Shawn re-opens his healing center, Doyle later takes her sick father to be healed by Shawn, stating "They blinked. Let them fire me."

She shows significant signs of a love for classic foreign films, even going so far as to put up posters of La Dolce Vita in her office. When Meghan reinstates Diana Skouris, she asks Diana if she has seen the movie; after a brief exchange on the superiority of subtitled films (as opposed to dubbed) Meghan welcomes Diana back, bemusedly saying Diana's appreciation "doesn't hurt your case."

Unlike previous leaders Dennis Ryland and Nina Jarvis, Meghan regularly spends time in Marco Pacella's theory room, a fact Tom commented on when Diana Skouris asked for information on Doyle. Doyle's management style is different than her predecessors, and she appears to lack the overt authority exhibited by Ryland and Jarvis, preferring a more informal approach. Diana later mentions to Tom that Meghan appears sweet on him; shortly after, the attraction of Tom to Meghan grows, and he is visibly upset when she seems to have died in No Exit and holds her tightly when he discovers her alive.

In "Daddy's Little Girl", Meghan visits Tom at home after a night out with friends, having seen "Be promicin positive" leaflets and realized that they are losing the war to Jordan Collier . The two kiss and have sex twice in the night, but the next morning Meghan informs Tom that they are still just friends. However at the close of the episode, she visits him again, kissing him and saying "very good friends." After being infected by a promicin-inducing virus in "The Great Leap Forward", Meghan's power emerges as she Transfigures her pen into a flower.