Maria Brennan's backstory revealed a shocking truth: she was originally born as a twin. Maria and her sister (whose original name was never revealed) were born 18 years ago to Amy and Dan Brennan, but the unnamed sister came out deformed. Dan, a plastic surgeon, callously refused to accept having a child with a deformity, and after Maria's sister was born, he made the decision to leave her out in the cold to freeze to death, while Maria lived on and was raised by Amy and Dan.
Throughout her entire life, Maria was unaware that she was actually a twin, and the film's events introduced Maria as being awkward and lonely, with fellow student Lily being her only friend since childhood. Maria suffered verbal abuse from Dan, while Amy was more kind to her, but put up with being cheated on and ignored by Dan, and it was later one night that Maria had her first encounter with her supernatual reflection. The reflection introduced herself as Airam ("Maria" spelled backwards), and originally served as a means of support and a self-esteem boost for Maria.
As the film progressed, Airam began to remind Maria of the many flaws of the people around her, stating that Dan didn't care about her and her feelings, and that Lily was a false friend and had been for many years, with the latter claim being shown beforehand when Lily didn't help Maria up during an ice skating lesson. Airam offered to help Maria with her problems, telling her to close her eyes and kiss her. After Maria goes to the winter prom and is bullied by a group of boys led by Mark, she takes up Airam's offer.
Airam takes over Maria's body, leaving an impression on her parents, as they were surprised by Maria's new demeanor. As she walked down the school corridor Mark insulted her again only this time she came up and advance towards him revealing that Mark was sexualy attracted to Maria humiliating him in the process. Airam then confronted Lily, but offered to allow Lily to teach her to skate. Late one night, while dining with Amy, Airam blasted her for covering for Dan, stating that Dan wasn't "working late" but actually engaging in an affair, resulting in Amy slapping "Maria" but later apologizing. After the confrontation, Airam was confronted by the real Maria, who was in the mirror and shocked over Airam being mean to her mother, only for Airam to state that she was being honest, while also saying that she was doing what Maria always wanted to do.
The following day at school, Airam watched Mark and the other hockey players practice, and afterwards, she followed Mark to the locker room and attacked him with a hockey stick, breaking his knee. Airam later appeared with Lily and showed off her skating abilities, with Lily appearing to be jealous of "Maria" improving, to the point where she took pleasure over "Maria" falling. Angry at who Maria thought as a friend take sadistic pleasure in her failure, Airam later moved towards Lily while staring at her ominously, prompting Lily to run away in fear, with Airam chasing after her. Airam sped up during her pursuit, which ended with Lily tripping on her own skates and falling on the ice, causing her to slide headfirst onto a block of pavement, killing her. After looking down at her indirect victim, Airam called 911 and pretended to panic over what happened, only to return to her villainous persona after hanging up.
Airam further established herself as a callous villainess during her confrontation with Maria, as she stated that Maria "wanted" her to do what she was doing, while also asking Maria if she really wanted Lily back and ignoring Maria's pleas to let her out into the real world. The villainess later went to Lily's boyfriend, Sean, and acted as a grieving friend, but later began seducing Sean and revealing her feelings for him. Though Sean was resistant at first, he gave into the seduction, leading to a relationship betwen the pair. Later on, while Sean and Airam were at a motel together, the former stated that the police were planning to talk to both of them. Airam attempted to talk Sean into not going, but Sean was insistent, stating that it had to be done for Lily, while turning down her seductive advances. Just as Sean was about to leave, the evil Airam struck Sean in the back of his head with a bottle, killing him instantly.
A flashback revealed Airam's true identity as Maria's deceased twin sister, and it also revealed her motive: revenge for being abandoned and left to die by Dan. She later appeared at Dan's office claiming that she drank too much, but it was after she was let in that she removed her clothes and demanded that Dan look at her and tell her that she was beautiful. Without giving away her identity, Airam asked Dan if he would love her if she was deformed, with Dan stating that he would. Knowing that Dan was lying, Airam grabbed a scalpel and slashed her father's throat, and afterwards, she called out for Maria, only to receive no answer. In the end of the film, Airam returned home and laid next to a dazed Amy (who had been traumatized due to Dan's actions), and the final scene ends with flickering reflections and a scene of Amy holding Maria and Airam in her arms.
- India Eisley also appeared in 2014's Nanny Cam as the evil Heather Lambert.