The only child of Matriarch Benezia. Liara was raised by her mother alone. She knew little of who her father was, only that it was another asari. Liara is a pureblood. a fact she speculates to be a reason why her "father" seemingly did not wish to be identified.
From an early age Liara became fascinated in the Protheans, seeing them as wondrous, mysterious figures. Growing up, she did not relish her role as Benezia's daughter and has shied away from her mother's life as an important figure in galactic affairs. Benezia's position meant Liara faced high expectations from everyone. Liara chose a career in archaeology to indulge her interests and to escape the pressures of being the daughter of such a prominent figure. Because of her work, Liara spent most of her time in content solitude.
Her work eventually took her to Knossos in the Artemis Tau cluster, to the site of a Prothean ruin on the mining planet Therum. When geth forces showed up on the world in 2183, Liara hid in the old catacombs and activated its barrier curtains. However, she accidentally suspended herself in an energy field, unable to move unless someone else comes along and frees her.
Following the exposure of Benezia's involvement with renegade Spectre Saren Arterius. Commander Shepard travels to Therum to find Liara T'Soni and discover what she knows. Liara pleads with Shepard's team for help when they find her, offering to explain her circumstances and means to be freed.
If Shepard pursues other leads first and significantly delays rescuing Liara, she mistakes her rescuers for figments of her imagination as a result of being stuck for so long. Nevertheless, she humors her "hallucinations" and answers their questions. She only realizes they're real when the squad reappears behind and close enough to release her.
Shepard's team soon learn that Liara is clueless on Benezia's activities as she hasn't even spoken to her mother in many years. When Liara asks why the geth are after her, a squadmate speculates that Saren may have wanted her Prothean expertise to help him find the Conduit. After a brief scuffle with Saren's forces and subsequent escape from the doomed ruins, Liara joins the Normandy crew.
Ostensibly her Prothean expertise and assurances of safety are her justifications for being aboard, but Liara becomes one of Shepard's possible squadmates, available for dangerous frontline situations. She is used to defending herself on remote digs—sites are often raided by privateers for artifacts—and in combat, she makes a formidable ally due to her near-complete focus on biotics.
As it turns out, Liara's knowledge of the Conduit isn't much at all, only that it was connected to the Prothean extinction. Half a century of dedicated research caused her to uncover telltale patterns that hint to an ancient galactic coverup - unprovable, but her gut feeling tells her otherwise. On her first debriefing aboard the Normandy, Liara shares her theory of cyclical extinction: the Protheans were just the latest in a long line of civilizations violently cast down after reaching their apex. Liara is surprised by Shepard's revelation of the Reapers ' responsibility in the Protheans' doom, but believes it to be true, as there was remarkably little evidence of the Protheans' existence—as if something or someone did not want the mystery of their disappearance solved.
Liara is shy and not used to lying, a trait Ashley Williams is tempted to take advantage of—"Want me to ask about her sex life? Might be illuminating." Regardless, Liara is viewed with suspicion by the rest of the Normandy's crew because of her connection to Benezia. To her mother's defense, Liara knows Benezia well enough to be astonished to discover she is working with Saren, and does not believe she could be aiding him of her own free will. Shepard can talk to Liara about her mother and discuss the reasons Benezia may have for assisting Saren, as well as asari culture
in general and the misconceptions surrounding Liara's species.
Liara is initially drawn to Shepard because the Commander was touched by Prothean technology on Eden Prime. Unfortunately, as Liara is used to isolation, she confesses she always seems to say something embarrassing around other people. When Shepard jokes about Liara sounding like she wants to dissect Shepard in a lab, Liara becomes flustered and claims she only meant Shepard would make an interesting specimen for an in-depth study, further embarrassing herself. Liara discreetly looks up Shepard's service history to learn more, worrying about making a fool of herself if she asks the Commander directly. Her scientific interest may become a romantic attraction that Shepard can choose to pursue.
Even if Shepard has other romantic interests, Liara still cares about the Commander, sympathetic to the nightmares Shepard suffers because of the beacon visions. Liara is very compassionate—she even feels sorry for Saren because he is losing his mind to indoctrination.
During the mission on Noveria, Gianna Parasini mentions to Shepard that Matriarch Benezia is visiting Peak 15. If Liara is on the Normandy and isn't with the shore party, a squad member suggests bringing her in to confront or possibly talk her mother down. Regardless of Liara's presence, Benezia has been indoctrinated beyond redemption and has to be put down. If Liara faces her mother, though, she personally receives her mother's proud approval during the latter's brief moments of lucidity. She last hears her "Little Wing" moniker from Benezia as her mother succumbs to her injuries.
Aboard the Normandy Liara discourages attempts at talking about her mother, though she opens up if Shepard presses the matter. She takes some comfort from the fact Benezia tried to stop Saren, no matter how the attempt turned out. She chooses to remember Benezia as she once was, not how she ended up.
As Shepard obtains fragmented visions from various sources during the search for Saren, Liara offers her melding abilities to try and make sense of the data. She constantly exhausts herself after each encounter, prompting frequent suggestions to report to Dr. Chakwas. but collects herself together long enough to explain what she saw. Once Shepard obtains the Cipher. the Mu Relay 's location, and the distress call from the Prothean Beacon on Virmire, Liara finally recognizes enough clues to determine the Conduit's location: Ilos.
“There's something compelling about you, Shepard.”
If Shepard pursues a romance with either Ashley or Kaidan in addition to Liara, she and the other party eventually force the Commander to choose only one. Liara doesn't understand much about human relationships, but she does make it clear she understands the concept of jealousy. If the other party walks out, she expresses relief that Shepard chose her, but feels sorry for her rival nonetheless.
Liara eventually reveals she has never been intimate with someone before and finds the idea a little daunting. She gradually comes to trust the Commander, feeling as if they share some special connection. However, she feels the times are too dark for them to give into each other and regrets having to make this sacrifice for the sake of the mission. During the Normandy's lockdown, she comes to Shepard's side to reassure the Commander, and they almost share a kiss before being interrupted by Joker.
When the Normandy escapes and is en route to Ilos, Liara comes to see Shepard in the Captain's Cabin, claiming she wants to spend the night. She is afraid she might never see Shepard again, though she's certain this is what she wants. Shepard's mood determines whether they consummate their love or not.
If the missions on Feros. Noveria. and Virmire are completed before rescuing Liara, a romance between her and Shepard becomes impossible due to the hectic pacing of subsequent events preventing meaningful interactions with each other.