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Anastasia "Dee" Dualla [du.ˈɑ.lə] is the former Communications Officer of Galactica and was the Executive Officer of the battlestar Pegasus prior to its destruction. At one time she was married to Lee Adama, but separated from him.
Dualla's father thought that her enlistment in the Colonial Fleet Reserve was crazy, and he viewed the military as a joke. She signed up anyway because she "wanted to believe in something." This rift with her father would continue throughout her service and the last time they spoke they got in a heated argument; three weeks later the Cylons attacked, and Dualla never got a chance to reconcile with him (TRS: "Final Cut"). His rejection of her career choice stems from traditional Sagittaron beliefs in pacifism, which Dualla does not share (TRS: "The Woman King").
At the time of the Cylon attack she monitors Colonial Fleet communications traffic. Dualla is among the first to notice the unusually high levels of shipboard malfunctions and failures aboard other battlestars (TRS: Miniseries).
After the Fleet's initial escape and pursuit by the Cylons, Dualla coordinates Fleet activities such as FTL jumps with Tactical Officer Felix Gaeta. In this responsibility, she discovers that Olympic Carrier fails to jump with the fleet after yet another jump (TRS: "33").
Due to his attraction to Dualla, presidential aide Billy Keikeya "volunteers" her to join an off-ship mission to Astral Queen (TRS: "Bastille Day"). Led by Captain Lee Adama, the mission is to attempt enlistment of prisoners aboard Astral Queen in resupplying Galactica with water following an act of sabotage (TRS: "Water"). During the mission, the team is taken hostage by prisoners during a jail break lead by fellow Sagittaron and political agitator Tom Zarek.
When a party of Cylons boards Galactica, Dualla suffers a concussion, but survives the engagement (TRS: "Valley of Darkness"). Later, Dualla aids in Laura Roslin's escape from Galactica after the President's arrest by covering up the tracks of their secret communications coordinating their movements in the Fleet, and getting Colonel Tigh to sign permission to close off a causeway which they use as an escape route. At this time, Dualla seems to take a greater personal interest in Apollo (TRS: "Resistance").
Dualla is assigned to give D'Anna Biers a tour around the battlestar as part of Biers' documentary of the ship (TRS: "Final Cut"). Lee Adama seems to return Dualla's personal attraction during a sparring exercise with the petty officer (TRS: "Flight of the Phoenix").
Keikeya, apparently attempting to solidify his relationship with the petty officer, proposes to Dualla, but she refuses. Keikeya later sees Dualla with Lee Adama on Cloud 9 and accuses her of leading him on. Shortly after Keikeya's accusation, four terrorists commandeer the lounge and its occupants and demand the surrender of Sharon Valerii. When a ruse by Admiral William Adama is discovered, the leader of the the terrorists orders Dualla's death. Keikeya intervenes and manages to kill the terrorist about to execute her, but is killed by him in return. In the same battle, Lee Adama is left severely wounded from a friendly-fire incident during an ill-fated reconnaissance by Kara Thrace. Dualla promises to watch over Lee Adama until he recovers in sickbay. When he finally regained consciousness, Dualla was so happy that neither of them noticed Thrace leaving the sickbay with a heartbroken expression (TRS: "Sacrifice").
A few months later, still involved with Apollo, Dualla assists in the counting of ballots for the Presidential election. Dualla conspires with Tory Foster and Saul Tigh to rig the election in Roslin's favor, indicating that she comprehends the disaster that would follow if Gaius Baltar is elected. Though the plot initially succeeds, Lt. Gaeta's curiosity leads to Admiral Adama's discovery of the duplicity.
Colonization of New Caprica
A few months later, Dualla has received a lieutenant's commission and is an officer now. Her transfer to Pegasus was approved on Founders' Day - the official groundbreaking of New Caprica City, but she is still trying to keep her relationship with Lee Adama from becoming too public.
On the night of Founders' Day, Lee Adama spends a night with Thrace. The following morning, however, upon seeing that Thrace and Anders eloped, Lee proposes to Dualla and holds her affectionately in public. Dualla is aware of his love for Thrace, but likely doesn't know that they slept together. However, she says that life is good at the moment and that they should make the best of it until the Cylons show up again. She tells Adama that this is the happiest state she has ever seen him in and agrees to marry him (TRS: "Unfinished Business (Extended Version)").
She subsequently serves as communications and executive officer on Pegasus, part of its skeletal crew in orbit around New Caprica. She answers the communication from Kara Thrace on New Caprica, who wants to ask Commander Adama for antibiotics for her husband. While Adama is on the phone, Dualla identifies sudden DRADIS contacts of a large Cylon fleet (TRS: "Lay Down Your Burdens, Part II").
Four months after leaving New Caprica, Admiral Adama decides to go through with a hazardous rescue operation. Dualla visibly disapproves of her father-in-law's decision to grant amnesty and a commission to Sharon Agathon and assign her as the liaison officer with the New Caprica Resistance (TRS: "Precipice"). Dualla tries to reassure her husband after Admiral Adama decides to take Galactica alone on the New Caprica rescue mission (TRS: "Exodus, Part I"). She appears visibly pleased when her husband defies orders and sacrifices Pegasus to save Galactica and the reassembled Fleet (TRS: "Exodus, Part II").
After the Second Exodus
Dualla returns periodically to her old post in Galactica's CIC after the Battle of New Caprica, but also has greater responsibilities in shepherding civilians on Galactica during a harrowing journey through a dangerous star cluster to a planet filled with edible algae (TRS: "The Passage"). Dualla and Samuel Anders are also witness to what appears to be both a feud and not-so-veiled affection between her husband and Anders' wife during a boxing match where Major Adama and Captain Thrace beat each other to exhaustion (TRS: "Unfinished Business").
After Cylons arrive at the algae planet, Dualla must shift her time to coordinate a defensive plan for the mysterious Temple of Five. She is ordered by her husband to rescue Starbuck after her Raptor is downed by a Cylon missile. Despite being quite aware of her husband's affair with Thrace, she rescues Thrace, repairs the avionics, and, with Thrace's guidance, flies the Raptor back to Galactica herself despite her own lack of pilot training as Starbuck's hands are too badly burned for her to fly ("The Eye of Jupiter", "Rapture").
Dualla confronts her husband about their marriage and its problems. She believes it to be a lie, but indicates she will not interfere if he chose to pursue his relationship with Kara Thrace. Adama breaks off his affair and reconciles (TRS: "Taking a Break From All Your Worries").
Dualla contracts Mellorak sickness as do many other fellow Sagittarons (housed as refugees on the battlestar) and - unlike other Sagittarons who regarding medicine as evil - seeks treatment from Dr. Michael Robert, a civilian doctor, because of her unspecified dislike for Doctor Cottle. When Dr. Robert is discovered to have killed the Sagittarons he treats, Karl Agathon rushes to her rescue and finds her out of danger, as Dr. Robert only targets Sagittarons outside of the military (TRS: "The Woman King").
When her husband chooses to defend Dr. Gaius Baltar in his trial, Dualla is incensed, and separates from him (TRS: "Crossroads, Part I"). Later, when Adama officially leaves Galactica to start his new life a civilian, the two embrace and he tells her that she "got the house", implying that their breakup is final yet, in the end, amicable (TRS: "Six of One").
She works closely with her estranged husband when, as Acting President, Lee takes command of the fleet during his father's emotional incapacity and threatens to execute Saul Tigh, Samuel Anders, and Galen Tyrol unless Number Three releases her human hostages (TRS: "Revelations"). Dualla addresses him as "Mr. President" when notifying him of incoming communication, but does not demonstrate any of the animosity, disapproval nor hostility toward him as she periodically did aboard Pegasus and the algae planet. Indeed, she appears to be quite pleased and proud of her husband, while maintaining a professional demeanor.
Finding the planet Earth in its devastated condition takes a heavy toll on her. Upon returning to Galactica from the initial visit to the surface, she seeks out Lee and the two spend a pleasant evening over drinks together. She returns to her quarters and speaks briefly with Felix Gaeta. Directly after he leaves the room, she pulls out her service pistol, places it against her temple, and pulls the trigger. A shocked Felix races back into the room; as does Diana Seelix. Gaeta and other crewmembers call for a medic, but it is already too late (TRS: "Sometimes a Great Notion").