|"In many ways, Billie Adams is both the most and the least successful of the Stage 2 SOR residents. On the one hand, she has absorbed her Stage 1 academic and physical training with an efficiency, and to a degree, that demonstrates her suitability for Stage 2. However, her behavioural adaptability is far less encouraging.
Adams grew up in post-Collapse Old Chicago, and her early experiences on the streets left her cynical and hardened, with a particular mistrust for institutional authority. Her impulses have frequently led her into conflict, bordering on insubordination, with her instructors. However, she has been retained in the SOR program due to her high competency, as well as her REFERENCE OMITTED AT YOUR SECURITY CLASSIFICATION.
Billie has shown an interest in subversive thought and organizations that must be carefully monitored. She has formed a quasi-familial affection for fellow Stage 2 resident AlexD, which can perhaps be used to moderate her more volatile traits."
|— dossier on Billie Adams, Tarsus Security Operations Residency (SOR) program|
After the Chicago attack, Billie became a secret agent of the Order and was the first student to learn of Tarsus' true purpose, which was to create a universal biomodification technology, which would be compatible with every human being.
After escaping the raid on the Seattle Tarsus facility, she was ordered by High Augur Lin-May Chen to investigate a possible cover up over a nanite plague cure in Cairo, where she met Luminon Saman. He recruited her into the Knights Templar, where she developed a zealous hatred for the biomodification. Alex met her again in JC Denton's sanctuary in Antarctica, and had an option to either kill her, knock her unconscious, or escape without confrontation. If left alive, she would appear later on, in the UNATCO HQ on Liberty Island, and would be hostile or friendly depending on Alex's past actions towards the Templars.
In hindsight, Billie's character profile was implied by cutscenes, background information available in the game and conversations with the JC Denton-Helios AI. While her personality profile was noted to be cynical and distrustful of authority, her motivations were evident from her early allegiance with the Templar faction in the Order. As Alex asked, "Why not get rid of nanotech and genetic engineering, the technologies that make people different from each other?" to which the AI replies, "Then you go down the path of intolerance, as your friend Billie did" It is implied in-game that Billie Adams compromised the location of the Chicago facility, then the Seattle laboratories. In the introduction movie, she displays a twisted need for excitement derived from danger. Billie was observed to be abnormally calm after the nanite detonation despite the surrounding panic. She leaped to the departing helicopter and cleared the destruction only moments before the facility fell to the nanite swarm. What promised outcome she believed in was unclear, given that she could not be a part of an organization that despised her for what she is, although the consensus was that her path was self-destructive.