Audience members of a “Peter Rabbit” screening who were expecting a family-friendly viewing experience were in for a surprise on Wednesday.

At Event Cinemas in Innaloo, Western Australia, the trailer for the upcoming R-rated horror film “Hereditary” played ahead of “Peter Rabbit,” a family film following the life of a mischievous rabbit. According to the Sydney Morning Herald, the preview was mistakenly shown in the theater and resulted in a panic from many of the parents and small children in the audience.

“It was dreadful. Very quickly you could tell this was not a kid’s film,” an audience member told the Australian newspaper. “Parents were yelling at the projectionist to stop, covering their kids’ eyes and ears. A few went out to get a staff member but she was overwhelmed and didn’t really know what to do. Some parents fled the cinema with their kids in tow.”

The viewer added, “A lot of the kids were upset. If you think back to your own childhood you remember things that scared you when you saw them for the first time. I still remember the first time I saw a robber on TV.”

The theater eventually shut off the trailer, offering guests complimentary movie tickets as an apology. A spokesperson for Event Cinemas said they were investigating how the mistake was made so it would not occur again.

Hereditary,” starring Toni Collette, Gabriel Byrne, Alex Wolff, and Ann Dowd, follows a family terrorized by ghosts after the death of a family member and has been described as one of the scariest movies of the year. The trailer sees Wolff’s character possessed by spirits while at school, a man on fire and a child trapped in bed while covered in ants.

The film hits theaters June 8.

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