Hedy drags Allie's body from the elevator to the furnace room in the basement and goes looking for a wheelbarrow (to presumably burn her body up in the building furnace). When she returns, however, Allie's body is gone. Frantically, Hedy grabs a heavy iron meat hook and goes from room to room looking for Allie, but Allie has crawled out of sight in an overhead air vent. Allie knocks a rat down on Hedy's shoulder, scaring her, but Hedy continues to search. Suddenly, Allie drops on top of Hedy and stabs her twice in the back with a screwdriver, killing her. In an epilogue, Allie is packing up some boxes of items in the apartment, including Hedy's photos of her twin sister. In a voiceover, Allie says,
Hedy's parents said that for years they tried to explain to her that her sister's death wasn't her fault but she never forgave herself for surviving. So every day, I try to forgive Hedy for Sam. Then I try to do what she couldn't...forgive myself. I know what can happen to someone who doesn't.
The final scene is a closeup of a photograph, comprised half of Hedy's face taped to the other half of Allie's face, making them look like one person.