And you won't believe what saved her from what could have been a much more serious injury...
The Aussie actress tells us that while filming an action scene for her upcoming flick Sucker Punch, she took a steel bayonet to the head!
"It was like this World War I rifle," Cornish explained at last night's Hollywood premiere of Limitless. "This guy was coming to stab me with a bayonet, and I duck and it kills the guy behind me. And so on this one take, the timing was just a little off because it was all so close and so precisely timed that the bayonet just stuck the side of my head when I went down."
"I didn't need stitches," she said. "I was actually saved by the metal hairclip that was in the side of my hair, because I remember when it hit I heard this, ting, like a metal-on-metal sound. But yeah, I had blood down my face. I had to clean up all the blood and keep going.
And Cornish says she didn't even mind the close call.
"It was awesome!" she laughed. "We were shooting this scene all day long and it happened halfway through the day so it was like a hit of adrenaline that I could take with me."