As the pressure of being a surgical student becomes overwhelming, Mary finds herself in dire straits and resorts to an unconventional job at a strip club to ease her financial burden. What she initially thought would be a means to an end spirals into chaos when Billy Barker, the club's mysterious owner, approaches her with a shocking offer: a staggering $5,000 for performing emergency surgery on a patient hidden away in the shadows. Hesitant yet desperate, Mary begrudgingly accepts.
The unsettling ambiance of the strip club shifts when she meets Beatress Johnson, a striking performer who has undergone extensive plastic surgeries to mimic the iconic Betty Boop. Beatress then entices Mary with another lucrative proposition, asking her to operate on her friend Ruby Realgirl at a veterinary clinic. Ruby’s odd request to have her genitalia removed and sutured into a doll-like state raises ethical alarms, but Mary's financial concerns overshadow her moral compass as she embarks on this grim new venture that drags her deeper into the underbelly of extreme body modification.
While beginning her surgical residency, Mary's talents draw admiration from her peers and mentors. However, her seemingly bright future takes an unsettling turn when an invitation to a networking party reveals the dark side of the medical profession. At this gathering, she finds herself subjected to shocking behavior from her senior colleagues, culminating in a horrifying act of violence from Dr. Alan Grant, a once-trusted teacher.
Feeling the weight of her shattered ambitions, Mary drops out of her residency and, in a shocking twist, uses Billy’s connections to abduct Grant. She takes him hostage in her apartment, transforming him into a gruesome specimen for her extreme surgical portfolio. Now known on the dark web as "Bloody Mary," she gains infamy for her unorthodox practices, blurring the lines of morality even further.
As the police probe into Grant's disappearance deepens, Mary becomes embroiled in a tangle of suspicion. Detective Dolor visits her again, disclosing that Dr. Walsh had a list of women with grudges against Grant, including Mary's name. In a bid to protect her, Billy takes violent action against Dr. Walsh, further entrenching Mary in chaos.
However, the situation escalates as Mary's condition deteriorates, and her actions become increasingly violent. When an encounter with evidence of Grant’s abuse leads her to lash out indiscriminately, she inadvertently kills a security guard in her fury. Meanwhile, Detective Dolor, torn between her being a victim or a perpetrator, endeavors to uncover the truth behind the sordid events surrounding Mary.
Tragedy strikes with the death of her grandmother, plunging Mary further into despair, especially when she discovers Billy in a compromising situation with one of the strippers. Consumed by jealousy, she retaliates against the woman with alarming precision.
As police scrutiny intensifies, Mary becomes engulfed in paranoia, terrified that the violent secrets of her past will be laid bare. Her fears crystallize when Ruby's husband, driven mad by his wife’s transformation, seeks revenge, igniting a chain of events that leads to a violent confrontation at Mary's home.
In a harrowing climax, she finds herself cornered by Ruby’s husband, and in a frantic struggle for survival, her own operating room morphs into a scene of tragedy. As she desperately tries to stitch her wounds, the sterile silence of the room becomes her final resting place. The police arrive too late to intervene, leaving the echoes of her tragic fall reverberating in the gloom.
