Happy Death Day

Theresa 'Tree' Gelbman, an entitled and casually cruel sorority girl, wakes up hungover on the morning of her birthday, September 18th, in the dorm room of a stranger named Carter Davis. She does the walk of shame back to her sorority, blows off a call from her father — it is also the anniversary of her mother's death — sleeps with the married Dr. Gregory Butler (her professor), and trudges through a self-absorbed day of small unkindnesses. That night, walking alone through a campus tunnel to a party, she is stabbed to death by a figure in a baby-faced mask.

She wakes up again in Carter's bed, hungover, the morning of her birthday. The day repeats. She brushes it off as déjà vu — but the killer is waiting for her again. Drowned in a bathtub. Hanged. Hit by a bus. Each death loops her back to Carter's dorm.

She tells Carter, and he believes her. He suggests she investigate every suspect she has and every place she goes during the day. She rules out her sorority sisters and her ex one by one, dying in fresh ways each loop. A hospital scan reveals her body retains the cumulative trauma of every death — the loops are killing her even as they reset.

She becomes convinced the killer is Joseph Tombs, an escaped serial killer being held at the local hospital. She infiltrates the building and corners him — only for the masked killer to murder her again from behind. She finally pieces it together. Her roommate Lori — sweet, helpful Lori, who has been baking her birthday cupcakes — was Dr. Butler's other lover and has been trying to poison Tree to clear the field.

Tree confronts Lori in their dorm room, refuses the cupcake, and during a vicious fight forces Lori to eat it herself. Lori falls from the window to her death and the loop breaks. Tree wakes the next morning, finally on September 19th, having reconciled with her father, her sisters, and Carter. The film closes with one last fakeout in Carter's dorm — she pretends she is still in the loop just to get one more laugh out of him, and then they begin the rest of her actual life.