Aside from being spotted on the streets of Vancouver, British Columbia, while filming the movie, the 31-year-old Dornan hasn't walked any red carpets or really talked about the role.
He did tweet on Jan. 1 from his official account, "looking forward to 2015," which hinted at the film's scheduled release next February. (That tweet was retweeted more than 5,000 times.)
This aura of mystery surrounding Dornan is a good thing, says Marcia Gay Harden, who plays his character's mother in the film.
"I think the point is to have somebody mysterious because if you have somebody with too much pedigree to them ... you can't stop thinking about the pedigree. You just can't. It's almost impossible in a film to do that. ... I think that would be very hard to do for that role, so I think it's good that he's a bit of a mystery."
Dornan had a recurring role on ABC's "Once Upon a Time" and starred in the Irish TV drama series "The Fall" as a serial killer who targets women. The show was renewed for a second season.
So, what can she share about him?
"He's beautiful. He's chiseled beauty and the camera eats it up. He's an Irish boy. ... A U.K.-based actor who has done a bit of film. He just had a baby (with wife Amelia Warner).
As for playing the mom of such a sexually charged character, the 54-year-old Harden says her scenes were more PG-rated.
"If you are not in the red playroom of pain and pleasure with some naked flesh in your face and a sex toy in your hand, the experience of shooting the movie is much like doing any other movie. I'm the mom. I'm momma Grey," she joked.
Harden is one of the stars of the comedy "Trophy Wife," airing Tuesdays on ABC.
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