While out on a fun night at a haunted house, a thin man with skull makeup on walked up to them and handed one of them a knife.
"Well, here, stab him," he said, handing her a knife, according to the police report.
The 29-year-old woman took the knife, which she thought was fake, and stabbed it into her friend's left arm.
"As she pulled back she realized that there was blood on the knife," the report states. "There was a hole in the victim's shirt and blood was squirting from the victim's left arm."
Her friend, 29-year-old James Yochim, was treated at a local hospital.
The stabbing occurred Friday at the annual Nashville Nightmare, an over-the-top, immersive haunted experience
According to the police report, the group of friends who attended the attraction Friday night thought that the entire interaction with the thin man was all part of the show.
"Keep in mind, we'd been chased by chainsaws, holding other weapons, all kinds of stuff all night and it was all fake," Yochim told the Tennessean. "So she stabs at me with it, and everything got really black."