Allison Janney keeps a ''lucky peanut'' with her at all times.

The 'I, Tonya' star has an unusual lucky charm - a silver peanut given to her by her good pal and 'I, Tonya' screenwriter Steven Rogers.

Explaining how it came about, she told People magazine: ''I've known him a long time. Whenever I was doing a performance he would always say, to me 'sparkle peanut' and years ago he gave me a tiny, silver peanut. So I'm gonna have that in my purse.''

And the 58-year-old actress was tapped to play the ''most horrible, atrocious mother'' in the movie by Steven.

She shared previously: ''My friend wrote the worst, most horrible, atrocious mother on the planet and then thought of me to play her. But I think he knew that I would have fun - not that she's fun, but that I would be able to embrace her and give her some humanity, because she's really a monster. That was the challenge for me playing this part is seeing these scenes and going, 'Who does this?'

''And then Stephen would say, well, he had interviewed Tonya Harding, and this is how she described her mother. She stands by [her claim that] her mother threw a knife at her. Her mother, you know, abused her physically and verbally, and these are stories that she gave us, and we didn't have the luxury of talking to LaVona Harding, because we couldn't find her anywhere ...

''But to be able to have talked to her in person I think it would have helped me. But since I didn't, I let go. I was like, 'Well, this is the character that is part Tonya Harding's version of other mother, part Steven Rogers's artistic license, and part me jumping in and giving her what I wanted to give her.' And so I felt a little freedom there. But she did exist, and now she's actually surfaced, funnily enough.''