Margot Robbie remembered playing a terrible prank on her babysitter during an interview on BBC Radio 2’s ‘The Zoe Ball Breakfast Show’.

The famous actress opened up about a wicked prank she committed as a child in Thursday’s episode. One was clearly so extreme that the babysitter “ran screaming out of the house.”

“We got a new babysitter. I wanted my old babysitter, Talia, who was like 16, to come back and I thought she was so cool,” Robbie told host Zoe Ball. She said that when she met her new sitter, she decided to protest in the most unusual way.

“Then a very old woman came in and I wasn’t happy with it and told me to take a bath,” Robbie said. “I didn’t want to and she was so grumpy that she was like, ‘Let me show you…'”

What happened next was probably a moment the babysitter will never forget.

“So I got a big knife and ketchup, and I sprawled naked on the tile, put the ketchup on, put the knife down, and waited about 45 minutes for her to find me,” Robbie recalls.

Robbie gestured to lie down next to a knife with fake blood all over his body.

Robbie’s “Barbie” co-star Ryan Gosling also joined the interview. He seemed obviously surprised to hear the story. (Related: Margot Robbie hilariously trips over the meaning of ‘Barbie’ during a live show)

Ball shook his head at what he had just heard, and Robbie repeated the pride he felt in that moment.

“But it was worth the wait!” Robbie said.

“Did she run out of the house screaming?” Ball asked.

“Yeah, yeah, yeah,” Robbie said.

“This Barbie is the ultimate naughty girl,” Ball captioned the clip on her Instagram page.