Credit: John Paschal/JPI (3)

Some days at work are just… murder.

 We won’t give away the surprise ending of the 1981 cult classic Happy Birthday to Me, but we will say that the thriller’s stars had very different reactions to it. For those not in the know, the slasher flick focuses on a high-school Ms. Popularity played by Little House on the Prairie’s Melissa Sue Anderson and a quintessential Mean Girl played by Young & Restless’ Tracey E. Bregman.

Originally, the killer running around bumping off high-schoolers was all set to be one character. But at the last minute, the filmmakers pulled a switcheroo. “I was stunned about the change in the movie,” Bregman told Anderson’s fan website. But whereas Anderson was bummed by the alteration, the Daytime Emmy winner was thrilled. “Sorry, Melissa. I loved the ending!”

Happy Birthday to Me marked one of Bregman’s first roles following her 1978-80 run as bad girl Donna Temple on Days of Our Lives. Since her character in the feature was also naughtier than nice, though, it wasn’t exactly a departure. In fact, the movie’s director “took one look at me and said, ‘You are it,'” she recalled, “even though he later nicknamed me Crazy!” (Catch a glimpse of Bregman in action in the trailer below.)

Happy Birthday to Me is on Tubi, Vudu, Prime Video and Apple TV as well as available through Roku. And if you’re looking for more thrills and chills this Halloween season, you’re sure to find them in the below photo gallery, a roundup of the scariest movies featuring your soap favorites, from Eric Braeden (Victor) to Melody Thomas Scott (Nikki), from Jordi Vilasuso (ex-Rey) to the late, great Jeanne Cooper (Katherine).

Video: YouTube/Unseen Trailers