'Fifty Shades': Who's Playing Christian's Mom?

Marcia Gay Harden joins the flick, out in 2015.

The Grey family tree is quickly filling up its branches and Marcia Gay Harden has found her spot on it.

With pop singer Rita Ora set to play Christian Grey's adopted sister and "True Blood" actor Luke Grimes cast to star alongside Jamie Dornan as his adopted brother in the "Fifty Shades of Grey" movie, Mama Grey is also now locked into place. Academy Award-winner Harden will play Dr. Grace Trevelyan Grey and Christian's (Dornan) adoptive mother, according to The Hollywood Reporter.

After a major casting shake-up earlier this fall (Dornan replaced "Sons of Anarchy" star Charlie Hunnam), filming for "Fifty Shades" kicked off over the weekend in Vancouver. On December 1, Dornan and leading lady Dakota Johnson (Anastasia Steele) were photographed on set. Both Johnson and Dornan were spotted filming a scene together at a coffee shop.

Eloise Mumford, Victor Rasuk and Jennifer Ehle join Dornan and Johnson in the flick, which chronicles the S&M love affair between virginal college coed, Anastasia, and her sexy billionaire beau, who has a proclivity for kink.

So, is Dornan, a former underwear model, cool with getting kinky on the big screen?

"I'm a fairly worldly guy," he told MTV News of the film's sexually charged storyline. "I grew up in a very liberal place. I'm not saying we had a playroom, but I'm not shocked by [the sex in the book]. It's essential to tell the story. I can't believe films that don't invoke the sexual side of it. So it works for me."

Originally slated to hit theaters August 1, 2014, the film will now open February 13, 2015. Sam Taylor-Wood is directing the long-awaited big screen adaptation of E L James' bestselling novel.