Rosamund Pike has revealed that she rehearsed sex scenes for Gone Girl on a child doll.
To be exact, a Dora the Explorer doll.
Her daughter's not gonna want that back...
Oh, and that's not all.
She only went and practiced in the garden, IN PUBLIC!
The 37-year-old also got violent with lumps of meat at a butchers to replicate Anne's killer instinct.
Appearing on the Graham Norton Show, Rosamund revealed her bizarre methods for getting into character.
I rehearsed with a Dora the Explorer doll in my back yard!
She said: "I'd never cut anyone's throat so I went to a local butchers and with great determination set about the carcasses with a Stanley knife in full view of customers.
"I rehearsed with a Dora the Explorer doll in my back yard, probably in full view of the neighbours!"
Each to their own we suppose!
She also revealed that she's a huge fan of techno and went to a rave when she was eight months pregnant.
"When I finished the Gone Girl press tour, which was quite a commitment, I was in New York, eight months pregnant and heard about a morning rave and I thought, 'That has my name on it'," she said.
"I was out with friends the night before and they were really up for it. Come 6am I'm ready and waiting and I'm the only one there. I thought either I can go home or I can just do this on my own. So I went in with the bump and it was just fantastic.
"When the baby was born there were no lullabies just deep house!"