Ambassador Donnel Udina is a human diplomat stationed at the Citadel. He is humanity's most recent ambassador to the Council races (the first was Anita Goyle) and is determined to advance human interests wherever possible. Udina is mistrustful or at least apprehensive of Commander Shepard, particularly after the Commander's induction into the Spectres. Udina often requires solid, irrefutable proof of anything before acting, a trait which often conflicts with Shepard's goals. Udina plays the political game, refusing to rock the boat if it might endanger his standing—and therefore humanity's—with the Citadel Council.
Mass Effect[]
Udina believes that humans deserve a Council seat and they should have it sooner rather than later. Initially he pushes hard for a human to be inducted into the Spectres, hoping that this will be the first step. He blames Shepard for the 'failed' mission at Eden Prime, fretting it might have cost them humanity's best candidate for the Spectres.
During the hearing against Saren Arterius, Udina realizes it was a mistake to bring Captain Anderson into the hearing, as their past history complicates things and Saren is cleared of the charges. He gets Anderson off the case and directs Shepard to meet Harkin for clues to exposing Saren. Once Shepard has become a Spectre, Udina's diligence manifests itself as a preference for playing things safe to look good in front of the Council. He doesn't even bother to thank Shepard for exposing Saren as a traitor.
When Shepard reports back to the Embassy in between missions, Udina unfailingly manages to find fault with the way Shepard gets things done. He only cares that Feros was saved because losing the colony would have been a political disaster, becoming incredibly upset if Shepard fails to save the colony, citing that the Commander's efforts should have been stronger, and he has plenty to say about Shepard's handling of the rachni on Noveria. After Virmire, he's also kind enough to report that, due to Shepard's constant talk about the Reapers, the Council is starting to wonder if Shepard is unhinged. However he sometimes will say that he disagrees with their view, and that it's more important that Shepard "gets results".
After Shepard convinces the Council of Saren's imminent attack on the Citadel, Udina tries to move in and take control of the situation, wanting to keep humanity at the forefront of the battle against Saren to prove their usefulness. However, Shepard isn't finished. The Commander tries to warn them that the Reapers are getting ready to invade and destroy the galaxy, but the Council is tired of listening to Shepard's 'dreams' about the Reapers. Udina wants to show that Shepard isn't speaking for the Alliance, and orders the Normandy's controls locked out, leaving Shepard and the crew grounded until further notice.
However, Captain Anderson offers to go behind Udina's back and help Shepard unlock the Normandy's systems. If given the choice, Anderson decides to countermand Udina's order directly, claiming the ambassador had made it personal, and knocks Udina unconscious to use his computer. Shepard is able to take control of the Normandy again and stop Saren.
Somehow Udina manages to survive the initial attack on the Citadel when Sovereign and Saren launch their assault. If the Council survives, in gratitude for the Alliance's efforts against the geth and in memory of the human soldiers who sacrificed their lives defending the Citadel, the Council offers humanity a Council seat at last. Both Donnel Udina and Captain Anderson are nominated to take the post. Shepard can recommend Udina, claiming humanity needs someone who will keep their best interests in the forefront. The Council are not quite as enthusiastic as they could be—they know Udina's style of working a little too well. Udina jokes that he's been holding back and vows to make humanity a powerful presence on the Citadel, united with the other races to stop the Reapers. If Anderson is nominated instead, Udina will object, declaring that "Anderson prefers to let his fists do the talking", before asking Shepard if they are sure with their choice of placing a soldier in a political role.
Should Shepard decide to let the Council perish, then Udina will promote a human chairman, to lead the Council and the other races against the Reapers. If Shepard has committed too many questionable actions in the past, Udina will push for an all-human Council and have humanity lead the galaxy against the Reapers. Shepard can nominate either Captain Anderson or Udina to chair the Council. This Council will confront the Reapers with the Alliance as the military forefront. If Shepard picks Anderson for his military experience, Udina will not object, admitting that Shepard makes a valid point and tells Anderson that he hopes he is ready for his new responsibilities.
Mass Effect 2[]
If Shepard nominated Udina, he becomes the first human Councilor, with Anderson as his assistant. Should Anderson be nominated for the Council, Udina becomes his personal adviser instead. If Udina is the human Councilor and the previous Council was left to perish, Shepard will be unable to regain Spectre status. On the other hand, if the Council was saved, Shepard can regain Spectre status, regardless of whether Udina or Anderson becomes the human Councilor.
Despite Udina's hostility towards the Commander, if Shepard had helped people in 2183, such as Samesh Bhatia, Udina will pass along their grateful messages to Shepard's private terminal aboard the Normandy SR-2.
Mass Effect: Retribution[]
In 2186, Udina is the human representative on the Citadel Council, with Admiral Anderson serving as his advisor. Because Anderson suddenly has urgent business regarding Kahlee Sanders, Udina fills in for Anderson's duties in ongoing trade negotiations.
Anderson's activites soon develop into an elaborate strike against Cerberus with cooperation from the turians. In the aftermath of the simultaneous raids against Cerberus holdings, Udina conveys his displeasure at the Admiral's "inappropriate diplomatic relations" with the turians. Because of the "political shit-storm" that would take Udina months to clean up, he threatens Anderson with a massive investigation on the matter. Anderson resigns instead and tells Udina to cram that investigation "up his ass".
Mass Effect: Inquisition[]
Being the human Councilor in 2186, he tasks Captain Bailey with investigating an office in Bailey's district, citing intelligence reports that factions within C-Sec have gone rogue, which Executor Pallin may be involved with. Despite Bailey's protest that he is not the right person for the job, Udina ensures him that he can be trusted and asks to report directly to him. Bailey returns with a datapad incriminating the Executor but claims that Pallin was just as shocked at the accusations as he was and that he did not survive as long as he has without being able to read people, knowing Pallin was innocent despite what the evidence claimed. Udina dismisses Bailey's concerns, claiming that Pallin was only shocked because he was caught and that the matter is now left to the investigators. Udina promotes Bailey to Commander and goes to deliver a report of Bailey's findings to the rest of the Council and to look for a replacement Executor.
Mass Effect 3[]
By 2186, Udina replaces Anderson as Councilor, if Anderson was originally nominated to the post by Shepard.
After the destruction of Arcturus Station and death of the Alliance Parliament and Prime Minister Amul Shastri, Udina is left the most powerful political figure in the Alliance government. He is furious at the Council's refusal to work together but vows to do his best. Agreeing with Shepard and Admiral Hackett’s plan to construct the Crucible, Udina uses all political channels to aid in the war effort. He institutes a draft in all Alliance colonies, pressures colony worlds and allies for resources and ensures Hackett is provided with the resources and manpower to restore the remaining Fleets. Udina also provides Shepard with a perspective on the other Councilors to help the Commander find a way to pressure them for aid.
During this time, Udina appoints the Virmire survivor, Kaidan Alenko/Ashley Williams, as the second human Spectre. He also submits a Council motion that converts a portion of Presidium docks into civilian emergency housing to accommodate the influx of refugees.
Despite all these, Udina is left helpless when the Council refuses to give the Alliance support in retaking Earth. Horrified and panicked, Udina grows increasingly frustrated and desperate to help his homeworld. He confesses to Shepard that he knew a lot of people on Arcturus Station on a first name basis, requiring a second VI to keep track of their birthdays and anniversaries.
Eventually, Udina's desperation leads him to a deal with Cerberus to instigate a bloodless coup of the Citadel, arrest the Council and force them to grant him the emergency power necessary to order all Citadel forces to Earth. The salarian Councilor instantly detects Udina's suspicious actions and acquires evidence of his dealings. The resulting rush to conquer the Citadel and silence the Councilor, as well as the vastly differing goals of Udina and Kai Leng, who is responsible for leading Cerberus forces during the coup attempt, leads to the coup degenerating into a massacre, with Cerberus issuing martial law on the Citadel and murdering both C-Sec officers and civilians.
Meanwhile, Udina leads the remaining Councilors to an escape vehicle that Cerberus had already destroyed, allowing Kai Leng to corner them. This plan is undone when Shepard beats Leng to the Council and seals the entrance, blocking Leng’s path. Leng, considering the mission failed, quickly abandons Udina to his fate. Meanwhile, Shepard confronts Udina, the Councilors, and Ashley Williams/Kaidan Alenko (who is acting as the Council's bodyguard) about Udina's treachery. In response, Udina tries to frame Shepard as being in league with Cerberus. In the resulting conflict, Udina is shot and killed by Shepard or the Virmire survivor. Later, when Shepard and Anderson are pondering Udina's reasons for the coup, they suspect that he may have been indoctrinated.