Iris was the identity used by an imprinted personality that had somehow been placed into the body of a young girl. Posing as the daughter of a dumbshow named Mr. Miller, Iris traveled with a group of actuals in search of a safe haven from the butchers and the "tech". During this time, Iris carried out several murders that were blamed on other people, including Whiskey and Mr. Miller, until an actual named Zone discovered the truth. During a violent confrontation, Iris was forced into an imprint chair, and the personality was wiped from the body and replaced by Caroline Farrell.
Sometime during the "thought-pocalypse", the personality that identified itself as "Iris" was imprinted into the body of a young girl. Uncertain as to how this happened, Iris found "herself" ultimately traveling with a dumbshow that "she" called Mr. Miller, her "father". Also around this time, as of 2019, Iris and Mr. Miller found themselves in the company of a group of actuals. (S1: "Epitaph One")
In 2019, Iris was among the group of actuals that discovered the L.A. Dollhouse sometime after her "father", Mr. Miller and been turned into a dumbshow. This got her placed under the care of an actual named Lyn while debates were carried out on what to do with Mr. Miller. Once inside the Dollhouse, Iris and Lyn discovered the community shower once used by the actives, and further found that it still worked and provided hot water. Under the guise of looking for, and using the bathroom, Iris separated from Lyn with the later deciding to make use of the recently discovered shower. Using the distraction, Iris made her way back to Lyn after procuring a weapon, and murdered Lyn by bludgening her with a flashlight. Iris then proceeded to "find" the body, and scream in terror to call the attnetion of the other actuals to avoid suspicion. (S1: "Epitaph One")
The circumstances which led to her inhabiting the girl's body are never explained, nor is the fate of the body's original inhabitant. Iris' age, gender and purpose are left largely unexplained, as she was quickly discovered and wiped. Nevertheless, she had time to murder Griff and Lyn, in an attempt to frame her "father", Mr. Miller, and secure the use of the Dollhouse's imprinting technology.
After exposure, Iris was forced into the imprinting chair and her personality overwritten with that of Caroline Farrell. As there was no backup, it is assumed this spelled "Iris'" death.