Didn't know 'I, Tonya' was a true story: Margot Robbie

Australian actor Margot Robbie said she didn't know her new movie "I, Tonya" was based on a real-life story.

Margot, 27, stars as former American ice skater Tonya Harding - who pleaded guilty to hindering the prosecution following an attack on her rival Nancy Kerrigan in 1994 - in the Craig Gillespie-directed film.

Speaking to Variety, Margot said, "I didn't realise it was a true story. I thought it was complete fiction, just a wacky story. And then I found out it was all true and I was even more fascinated.