At some unknown point in time J. Forman started working at Glenwood Springs Psychiatric Hospital. She killed several patients there and fed on their brain fluids. She would make their deaths look like suicides to cover them up.
She attacked and killed a patient killed named Susan Fletcher after terrorizing her for an unspecified amount of time. She also killed a patient named Annie before she killed Susan.
The boys are admitted into the hospital and subjected to thorough examinations by Nurse Forman. Dean attempts to lay some ground rules with her, calling her "Nurse Ratched" and warning her not to try any "soul-crushing, authoritarian crap" on him. "Okie dokie," she replies with a calm smile. She secretly poisons them during the examinations due to knowing they are hunters so they can have hallucinations and make them not solve the case.
A few days later she kills a patient named Ted and makes his death look like a suicide. She made it look like he hung himself. She later catches Sam and Dean in the morgue where they were examining Ted's body. At a loss for an explanation of why they are in the morgue, Dean decides that dropping his pants, raising his hands in the air and yelling "Pudding!!" is the way to go. She only barely reacts and then shoos them out the door.
Nurse Forman later tried to feed on and kill another patient named Wendy. Before she could kill her she was interrupted by Dean and Martin. They see the nurse's wraith reflection in the mirror and realize she's in the process of sucking Wendy's brains out. She attacks them and gets the best of them both, but Martin manages to slash her with the silver weapon and she runs away. As she escapes down the hall, she tells the orderlies that two patients attacked her in Wendy's room. In the room, Martin discovers that Wendy is still alive and yells at disoriented Dean to go after the wraith. The orderlies rush in and Dean finally gets up and runs as Martin holds them off.
She then tried to fed and kill Sam while he was confined to a padded room and was bound by wrist and ankle restraints. She produces her spike and is preparing to stab Sam when Dean bursts in, still disoriented. She batters him for a while and gets dangerously close to skewering him, but he manages to grab her spike and break it. She recoils screaming and he grabs the silver-plated letter opener and plunges it into her chest. His vision re-aligns as he focuses on her lying dead. He releases Sam's restraints as the hospital's alarm sounds and they escape the facility.