Actors dressed as Islamic State (ISIS) militants created panic at a shopping mall in Tehran on Monday night, the Washington Post reported.
The actors reportedly showed up on horses with fake guns and swords and were shouting "Allahu Akbar".
The point of it all was to promote the film Damascus Time, which is about the terror group kidnapping an Iranian father and son while they travel to Syria to deliver aid.
Some realised it was a prank; others ran for their lives.
Not so surprisingly, it didn't go down so well. The stunt received a lot of heat on social media.
"I was under impression that someone is going to be in red beard standing outside [the mall] so that people can take pictures," director Ebrahim Hatamikia is quoted as saying by the Washington Post.
"I didn't imagine there would be a horse, crowd, and shouting inside the complex, I wasn't aware," he added.
Watch video of the stunt here: