Horror hit The Devil Inside had millions of movie goers shaking in fear when it topped the U.S. box office earlier this year, but RadarOnline.com has exclusively learned that one of the film’s stars is far less frightening in real life than on the big screen.

Guests at the 220 Fitness 1st Year Anniversary Party in Santa Monica, Calif., were surprised on Thursday to spot the woman of many a nightmare, Maria Rossi - the mother who killed three church members during her own exorcism, according to the scary tale - in the flesh and blood.

"Wow, this is scary, this place is packed. I thought I was the scary one!" joked Suzan Crowley, the British actress who played Rossi on the big screen, when she joined the crowds celebrating the success of the state of the art gym.