| "I once thought I could save the world... now look at it"
— Spoilers for Deus Ex: Mankind Divided follow!
The famous and mysterious Eliza Cassan is almost a celebrity in her own way, being the easily recognizable face of Picus TV. She delivers news 24/7 and seems to have an almost uncanny grasp of current events, though many remark that she seems to always deliver information with an ideological or biased slant.
Jensen finds out from Zhao Yun Ru that Eliza is somehow connected with the conspiracy and the attack on Sarif Industries, and sets out to confront her in Montreal. Upon arrival he finds a strangely deserted Picus headquarters, but eventually reaches Eliza's office.
There Eliza reveals she has been following Jensen for months and has some special interest in him, but cannot give him the information he seeks for some unknown reason, and tells him to leave. Jensen attempts to force Eliza to come with him in his need for answers, only to find that "Eliza" he holds by the arm dissolves away, revealing the image is actually an extremely sophisticated and lifelike hologram. The whole situation is actually an elaborate trap, as once "Eliza" disappears Belltower Spec Ops soldiers swarm the building, looking for Jensen.
Jensen refuses to give up and continues hunting for Cassan. Pritchard informs Jensen that the advanced holo-cloud was accompanied by massive power spikes originating from an apparent secret sub-basement of the building. Jensen eventually reaches these lower levels, and tracks down Eliza to a hidden chamber deep underground.
There, he discovers that the famous celebrity newsreader is actually an advanced artificial intelligence, created and designed for the purpose of controlling public information and shaping mass discourse, and the eventual goal of control and manipulation of all available information. The extremely advanced AI is programmed to guide public opinion to certain ends and was created by the conspiracy for this purpose. Jensen presses her for more information, but they are suddenly interrupted by the arrival of Eliza's guardian, Yelena Fedorova, with whom Jensen is forced into battle with.
After Jensen kills Fedorova, Cassan divulges that Isaias Sandoval is also personally involved, and gives him a recording as evidence. Jensen then escapes from the Picus building.
Jensen meets with Eliza once again at Panchaea. After he has disabled the Hyron Project and reached the central hub for the universal signal, Eliza will contact Jensen. She explains that the universal signal can be used to broadcast a message to the world, explaining what really took place. However, whereas Hugh Darrow had a prepared message in place, it's ultimately up to Jensen what gets sent out, and he can select a different message if he so chooses.
Eliza explains that Darrow's message reveals the whole truth behind recent events (including the Illuminati's involvement), warning of the dangers of augmentation and urging humanity to cast it aside. David Sarif has a different message in mind and wants to frame Humanity Front for the signal broadcast, thus turning the tide against the purists and paving the way for further development of augmentation technology. Bill Taggart (representing the Illuminati) wants to expose most of the truth behind recent events, excluding any reference to the Illuminati's involvement, thus leading to increased regulation of augmentation technology and therefore a significant reduction to the threat it poses to the Illuminati's continued control. There is also a fourth option as Eliza explains it - cause the Panchaea facility to self-destruct, thus killing all of the gathered world leaders there - Sarif, Taggart, Darrow, and even Jensen himself. This will free mankind and allow it to make up its own mind about augmentation, without anyone spinning events to further their own agenda.
In 2029 Eliza's style has changed with an intricate high rise hair style and clothing without the frilly collar as seen in the previous game. She still portrays the news with a suggestive negative tone towards augmented people and will often comment how the effects of "the incident" two years ago still deeply affects her. While on air she often uses subtle methods in her usage of words to portray augmented people in a negative tone while not actually saying outright negative statements. Examples of this include the story about an augmented man who supposedly crashed a commercial plane and when she conducted an interview with Talos Rucker of the Augmented Rights Coalition. However, during Adam's second visit to Prague, he can come across a side mission which reveals that the Eliza Cassan on TV is a different version from the one he dealt with in Panchaea.
It is revealed during the side mission that when Adam got to the universal signal and made his choice, the Eliza that was there got cut off from the rest of the world. Realizing this, the CEO of Picus News, Morgan Everett, changed over to a backup version of Eliza (who never met Adam) to continue giving out the news, but knew the previous one was still out there somewhere. When she contacted Adam, originally as Helle because she could not remember who exactly she was, she asked him to retrieve old memories to restore her. During this retrieval, Adam came across some men sent by Everett to also recover the memories to prevent the "real" Eliza from becoming more powerful and therefore, harder to stop.
Once Adam connects Helle to the memories, he learns it is Eliza, who reveals who and why she used Helle's image up to that point. Helle had been one of the women connected to the Hyron Project and when Panchaea was destroyed, her fear and pain was the strongest and therefore left an imprint on Eliza's memories. She reached out to Adam because, being there at the time of the destruction, she felt the process had started with him and therefore he should help "define" her as she has now become a full AI. She will then ask Adam what should she do, and he can either tell her to hide, fight, or make her own choice if she's truly sentient. Whichever advice Adam gives, Eliza thanks him. Later on, during Martial Law, Eliza will cause a distraction by blowing up a turret to help Adam sneak into Dvali territory and appears to show attachment, commenting how she does not want to lose him again.
- ELIZA was a computer program written by Joseph Weizenbaum between 1964 to 1966, an early example (by modern standards) of primitive Natural language processing. ELIZA operated by processing users' responses to scripts, the most famous of which was DOCTOR, a simulation of a Rogerian psychotherapy. Using almost no information about human thought or emotion, DOCTOR sometimes provided a startlingly human-like interaction.
- To hint that Eliza is not real, the Deus Ex: Human Revolution team decided to add pink, a color not found anywhere else in the game, to her outfit.
- The first room that Jensen looks for Cassan in is room 404, a reference to the HTTP Error Code 404, "file not found" to further imply she is not real.
- On the way to Eliza and 802-11, there is a scrolling news ticker above the door in the Funicular. One of the items is: "Holo-personalities untrustworthy? Yes, says noted psycho-sociologist..."
- The second room that Jensen goes to is room 802-11, a reference to the IEEE 802.11 standards, better known by the trademark WiFi.
- Eliza's name is a reference to the influential American director, Elia Kazan: famous for his introduction of realism and method acting to American cinema; highly politicized films and views; and making actors such as Marlon Brando and James Dean stars.
- Despite not being an actual human being, Eliza seems to have a fair range of emotions, such as what could be describe as confusion and shame when she assists in hiding the Sarif scientists. Dialogue with the recovered "original" Eliza AI in Mankind Divided also suggests a newfound sense of desire, personal attachment and defiance, something she was yet able to demonstrate in 2027.
- Eliza displays a particularly great interest in Adam Jensen, and is much more personable, emotional and arguably more honest when conversing with him. If the player chooses to cause Panchaea to self-destruct, she will tell Adam that is has "truly been a pleasure" to know him.
- Ironically, she sounds more human when broadcasting and more robotic when not.