Jaimie Alexander has revealed what happened when she suffered a setback while she was filming Thor: The Dark World in September.

"It was raining, it was dark outside, it was like 5 in the morning — and I went down a metal staircase and slipped and slipped a disc in my thoracic spine and chipped 11 of my vertebrae," she told the New York Post.

Alexander, who plays Lady Sif in Marvel's Thor had to take a break from production for weeks in order to recover, reports Contactmusic.com.

She tweeted about the injury not long after it happened letting her followers know she was lucky enough that the injury didn't leave her paralyzed.

https://twitter.com/JaimieAlexander/status/267274985620525057" data-datetime="2012-11-10T14:38:16+00:00

Thor: The Dark World is scheduled to hit theaters November 8, 2013.