Maggie Grace has signed on to play Irina in Breaking Dawn

Lost’ and ‘Taken’ actress will play a ‘vegetarian’ vampire who turns on the Cullens.

With production set to begin very soon, “The Twilight Saga: Breaking Dawn, Part 1″ continues to add members to its already-crowded cast.

Last month we learned that “The Pacific” actor Rami Malek had joined the “Dawn” ranks in the role of Egyptian vampire Benjamin. On Monday (September 27), it was reported that “Lost” and “Taken” actress Maggie Grace has signed on to play “vegetarian” vampire Irina.

A rep from Summit Entertainment confirmed the casting to MTV News, and the original story appeared first on Deadline.com.

So who is Irina? Those familiar with Stephenie Meyer’s source material will recall that she is a member of the Denali coven, one of the only other “vegetarian” vampire covens and allies with the Cullens — that is, until Irina blames the family for the death of her former lover, Laurent, and vengefully reveals a Cullen family secret to the Volturi.

The other “Dawn” newbie, Benjamin, is a member of the Egyptian coven who comes to help Bella and the Cullens battle the Volturi. Benjamin is a young vamp blessed with the special ability of controlling the elements (à la Storm from X-Men), though he has yet to fully master his powers.

“I think it’s going to be great,” Rami told “ET” of his joining the cast last month. “It’s going to be super exciting, and I’m thrilled.”

Summit announced in June that “Breaking Dawn” would be divided into two parts; the first of the two films is scheduled to hit theaters November 18, 2011, and the second on November 16, 2012.