Liara T'Soni
Role:
To say that Liara has a role to ME3's plot is an understatement. She is one of the driving forces of the game. Her resources as the Shadow Broker allow her to gain intel for numerous missions. Liara can act as a replacement mission-unlocker for most characters who were either killed or not recruited in ME2. She can allow Shepard to gain access to the Forum of Matriachs on Thessia to convince the asari leaders to become more active in the war. Liara also helps Shepard either take over or destroy Cerberus, and the evidence she brings before the Citadel Council helps uncover the truth about the Crucible, Leviathan of Dis, and various galactic government secrets. Through massive funding efforts, acts of extortion against corrupt corporations, and trading of information, Liara single handedly provides the Alliance, Hierarchy, Matriarchs, Salarian government, Tuchunka Clans, Hanar, Volus, and Elcor governments, with the ability build almost double their dreadnought, cruiser, and carrier numbers. The list of things Liara helps Shepard achieve is endless.
Recruitment:
Liara went to the planet Klencory, after Kumun Shol (ironically) sent a request to the Shadow Broker for information on the best Prothean experts in the galaxy. At the dig site for only a few weeks, Liara helped lead the archaeologists in excavating large sections of the Prothean crypt. When the Reaper invasion started, Shol sped up operation significantly. Shepard, after meeting with the Citadel council, goes to Klencory to investigate Shol's claims of Prothean technology buried there, and is surprised to find Liara amongst the other archaeologists. According to Liara, Shol should have called in more specialists sooner, but his fear that many Prothean experts were undercover raiders kept him from doing so.
Missions:
Liara provides briefings and debriefings on several missions throughout the story. Her identity as Shadow Broker is brought into question during her mission “The Broker” and she is the overseer of the “Shadow War” campaign – a private and covert power struggle between the Shadow Broker and Cerberus near the end of the game. She also provides Shepard and company with several (side) quests throughout the story.
Liara has one non-combative mission that comes up in Mass Effect 3, known simply as “The Broker”. During this mission, Cerberus leaks information to the Citadel's press that much of the Reaper-war's funding is coming from the Shadow Broker – a shady organization seen by most as being no better than Cerberus. The Council themselves publicly do not support either organization-- though there are rumors that most of the councilors have made deals with either Cerberus (if human council) or the Shadow Broker (if old/new council) in the past. At risk of losing the galactic support she worked so hard to build for the war effort, Liara confides in Shepard as to what route she should take in convincing the Council and other galactic governments that her support is genuine. Shepard can convince Liara to keep her Shadow Broker identity a secret, or to come out publicly as the Shadow Broker in an attempt to gain public trust.
If Shepard believes that the Shadow Broker should remain anonymous, they will decide to contact each of the governments and organizations individually via hacking their communications, to either threaten, bribe, or deal her way into their acceptance.
If Liara threatens them, the Shadow Broker forces the governments to accept her support, or risk their most embarrassing personal secrets to be revealed in the form of extranet videos beamed onto the Citadel's digital advertisement boards. Depending on which government Liara is specifically targeting, the specifics of her threat will change – for example, if she is confronting the Alliance over the radio, then Liara will threaten to release information about unknown WMDs embedded in probes that were sent into asari or turians space during the first contact war. However, if Liara is confronting the Hegenomy, she will threaten to release video files of the Hegemony okaying slave raids inside turian space – etc etc. This grants her the most trust from the governments, and they accept her offerings of funding for building ships.
If Liara bribes the governments, she does just that -- promising them valuable information for after the Reaper war. This gains her minimal trust from each group, and they only accept a few of her resources (ships, information, etc).
If Liara deals her way into the governments' trust, she provides them with valuable information that they have long sought. This allows them to trust the Shadow Broker enough to accept fleets to a certain extent.
If Shepard convinces Liara to come out as the Shadow Broker, Liara will order some of her mercenaries to join her on the Normandy, and escort her to the Citadel. Shepard will send a message to the Citadel that he has the Shadow Broker, and will bring her before the Council. The Council agrees to a private meeting with the Shadow Broker, provided that other governments are not permitted to attend the meeting.
When Shepard exits the Normandy, Liara goes with him, surrounded by her own security agents. A small group of C-sec officers take Liara up to the Citadel Tower to meet with the Council-- hoping not to attract attention by keeping the meeting small.
The Council at first believes Liara's identity to be some sort of joke, but Liara then meets with each councilor alone, and convinces them with sensitive information that only they could know – (information about Spectres working for the previous Broker in exchange for Council approved secrets). The Council then begins a formal inquiry as to how Liara became the Broker – and she tells them, adding that she has not performed any assassinations in the past six months.
The Council debates arresting Liara, but she threatens their secrets to go public, and the Council ask why they should trust her. Shepard intervenes:
Shepard can say that Liara trusted them with her secret, now they should trust her to help the war effort.
Shepard can say that the Council doesn't have a choice in allies, and that the Shadow Broker is a powerful ally.
Shepard can say that Liara will dump every dirty secret they've ever kept from the public onto the extranet.
The Council agrees to allow Liara to continue supporting the war effort, and her alter ego changes from “The Shadow Broker” to “The Broker”. The Council makes a public moral boost of their new found ally in “The Broker”, and the other governments quickly fold into the temptations of working publicly for The Broker. It becomes a public secret that the Shadow Broker and The Broker are the same entity, but most people believe that the Citadel managed to track down the organization using Spectres, and now controls the old Shadow Broker networks. In reality, the Council knows that even with Liara's identity revealed, they are still in her dept – and would be risking more than their lives if they ever betrayed her.
After Kai Leng detonates explosives in the Citadel's private hangar bay, causing an enormous amount of damage, killing several political figures, and shaking the united-races' faith in the Council for security, and humanity for trustworthiness, all available Citadel Spectres are brought before the Council to investigate and stop Cerberus's continual existence (Shepard, if a Spectre, is also amongst those Spectres).
If Liara revealed her identity as Broker to the Council, they will seek a private meeting with her (and Shepard) to seek out and destroy the terrorists. Liara will explain that she is already formulating plans of attack. The Council wishes for the fight to stay covert, but for the defeat of Cerberus to be made public, in order to restore faith in the Council (who plan on fabricating a story about how their Spectre teams took down Cerberus).
If Liara did not reveal her identity to the Council, she will hold a meeting on her Shadow Base with all of the characters (squad-mates, ex squad-mates, etc) who know of the base's existence.
Jack/Miranda/Jacob/Randall will explain that decoding transmission signals from Cerberus outposts in the Terminus system revealed the location of one of Cerberus's main base's, a space station called “The Barn” (Randall will be familiar with the place) which is a bio-engineering lab. If they take down the Shadow Base, Cerberus will be greatly financially damaged, and resource-weakened. Shepard and company might also find out what Cerberus is planning aboard the base – and where other Cerberus bases might be located.
Liara decides that she will remain on the Shadow Base for the duration of what she has now designated “Operation: Shadow War”, her ambiguous war with the Illusive Man, while the galaxy is right in the middle of the Reaper war.
From this point onward in the story, Liara will be found on her base. The only way for Shepard to activate “Shadow War” missions is to go to the Shadow Base, activate the galaxy map there, and select the available quests.
If Shiala survived ME1 and Shepard completed the side quest “Investigate ExoGeni”, Shiala can replace Liara as a temp squad-mate for the rest of the game.
[Note: Liara stays on the Shadow Base even after the assault on Cronos Station. She is no longer an available squad-mate, until the final assault on the Reapers. I did not do this to be cruel to Liara fans – but because it made sense with the story. On top of that, by this point in the story (apart from side quests) there aren't many main missions left, and for most of them Liara is available]
Potential love interest:
Liara (if not romancing Shepard) initially finds Javik to be an exciting and mysterious man. However, her friendly inquisitions into his life are often met by the Prothean's grumpy, even rude replies of distain and bitterness. While Liara insists (unconvincingly) that she is not attracted to Javik, Mordin Solus theorizes that asari are naturally attracted to Protheans, just as salarians, turians, batarians, and humans are attracted to asari.
Unfortunately, Javik's cold attitude continues for much of his time aboard the Normandy, and while he continuously reads and corrects Liara's notes on Prothean life, culture, and beliefs, he is rarely kind to her. And yet, Liara notes, Javik talks to her more than any other crew mate. One time, when Javik is particularly critical of Liara's note taking skills, she becomes angry, and reveals that she is disappointed that he, as a Prothean “doesn't have all of the answers”. Javik is taken aback by the notion that to the modern cycle, Protheans are thought of as mystical and almost omnipotent – since their artifacts gave most races the ability to achieve FTL technology.
After the end of the “Hidden Wards” mission, Javik becomes severely depressed (though he tries to hide it). Shepard can suggest that Liara talk to him, and Liara will reveal that she does find Javik attractive-- not because of the Prothean-asari natural attraction, but because she always idolized Protheans, even in her youth, and has come to the realization that they are as relatable as any other race.
Shepard can suggest that Liara seek a romantic relationship with Javik.
Shepard can suggest that Liara keep her relationship with Javik friendly.
Shepard can suggest that Liara maintains a professional relationship with Javik.
Liara will follow Shepard's advice. If she survives the final assault against the Reapers, Liara's epilogue can depend upon the kind of relationship she had with Javik.
Ironing out variables:
If Shiala was killed in ME1, then there is no replacement squad member for Liara after the assault on Cronos Station.
If Shepard romanced Liara in ME1, romanced Miranda in ME2, then romanced Liara again in Lair of the Shadow Broker DLC, the two women will confront Shepard when he makes his first rendezvous with the Shadow Base. Shepard must choose between which LI (if any) he is interested in pursuing a relationship with. Whichever Shepard chooses, the other will show subtle signs of jealousy, though they will not confront each other.