Signature Theatre cast members in dress rehearsal for “Sweeney Todd” in Arlington, Va. (Susan Biddle/The Washington Post)

Most people are familiar with the ballad of Sweeney Todd, told famously in Stephen Sondheim’s 1971 Tony Award-winning musical. A vengeful barber teams up with an equally macabre baker to turn his customers into meat pies; blood and gore and lively madness ensues.

Students at Saint Kentigern College, a private school in Auckland, New Zealand, were determined to do right by this tale in a musical production this week. The head of the school, Steve Cole, told TVNZ that they wanted to make the show “as realistic as possible.”

So realistic that some real blood was shed on stage.

Two 16-year-old students’ necks were cut with a prop during an opening night scene earlier this week, leading to their hospitalization. The actors were mimicking Sweeney Todd’s murder method of choice: slitting his unsuspecting customers’ throats.

The students’ fates were fortunately less dire. They have both been discharged from the hospital and are in stable condition, though one suffered serious injuries.

Speaking to radio station Newstalk ZB, Cole said the cause of the incident was a real cut-throat razor that had been wrapped with duct tape and cellophane, “bound in all sorts of things.”

“It was very non-sharp, blunted, and had been through all sorts of health and safety checks,” said Cole, who was perplexed by how it all happened. “It was a very unfortunate mishap.”

The razor was used at eight dress rehearsals in January without incident, the New Zealand Herald reported.

A police spokesman told the Herald that while the department is conducting an investigation, “It’s not a criminal inquiry. In this instance the play is not the reality.”

The owner of the antique shop where the razors were purchased, who spoke to the Herald on the condition of anonymity, recalled that the teacher who bought the object was “a really nice chap” who inquired about covering up the blades.

The razors sold for about $40, and the teacher mentioned that they would be used for a production of “Sweeney Todd.”

While Thursday’s performance was cancelled, Friday’s show is supposed to be performed as scheduled. The show must go on.

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