Most people call them Karens, but Upper Cape Cod Regional Technical School junior Abby Morrison suggests another name for “the person you don’t want to interact with at a grocery store:” Rosemary.

Morrison, who lives in Wareham and is studying environmental science, plays Rosemary in the Upper Cape Tech Canalside Players dinner theater production of Nathan Hartswick’s “Murder Café,” playing Thursday, Jan 6. and Friday, Jan 7. at 7 p.m. A brunch show on Sunday, Jan. 8 at 12 p.m. is sold out. All of the food at each show will be prepared and served by Upper Cape Tech’s culinary students.

Upper Cape Tech’s Canalside Dining Room will serve as the titular “Murder Café,” where Rosemary is killed offstage while celebrating her birthday with her four sisters. (Yes, the name of the restaurant is Murder Café. It’s written on the prop menus, and there are special sound effects that play every time the name is said). Morrison isn’t torn up over her character’s death, since Rosemary is nasty to everyone she meets. 

“I’ve had firsthand experience with people like that,” she said.

To play Rosemary, the normally easygoing Morrison thinks of rude customers she met during her summer job at Water Wizz of Cape Cod. 

Besides being mean, she said the hardest part is screaming offstage loud enough for the audience to hear.

“It’s really awkward,” she said. 

When an amateur detective proves useless, it is up to the play’s audience to catch the killer. As coffee and desserts are served, the audience will interrogate the cast and vote on who they think the murderer is. 

“It’s got great jokes, great laughs,” director Bobby Genereau said about the show. “It’s got a murder mystery element. It’s a lot of fun. It presents a different element to the kids’ acting.”

Most murder mystery dinner shows are ad-libbed, but this one is primarily scripted. Unlike most school plays, the student cast will not be on stage. All of the play’s action will happen in the restaurant, right in front of the audience. 

“It’s challenging but it’s also really fun,” Morrison said. 

Morrison also plays Rosemary’s sister Melanie, depending on what cast is performing. The “mellow” Melanie, she said, is the opposite of the “aggressive and abrasive” Rosemary.

“It’s kind of hard to switch from one character to the next,” she said, “but it’s nice to have that balance at the same time.”

Morrison wants to become a marine biologist, but she would love to pursue acting on the side. 

Sophomore Nevaeh Fernandes, of Wareham, is studying culinary arts, but she won’t spend the show in the kitchen. She plays Valerie, a valley girl who is the ditziest of Rosemary’s sisters.

“She’s kind of like me in some ways,” Fernandes said, “because I’m also on my phone a lot and sometimes I don’t pay attention.” 

Fernandes loves horror movies, murder mysteries and valley girl movies like “Clueless.”

“It’s fun getting to try that out for myself,” she said. 

Tickets to “Murder Café” are $40 and can be purchased at https://m.bpt.me/event/5655838.