The British-American drama Downton Abbey continues to move forward from season three. In the TV show's latest move, actor Tom Cullen has officially signed on as Lady Mary's (Michelle Dockery) future love interest, in lieu of Matthew's (Dan Stevens) surprising death via car crash to sadly end season three.

The PBS network has confirmed on its website that Cullen, 27, will play the part of Lord Gillingham, a longtime family friend of the Crawleys that Mary has been acquainted with since her childhood.

"I can announce that I'm in the new season four of Downton Abbey. So excited. My heart is beating a little too fast," Cullen confirmed to his followers via Twitter.

Cullen's prior accomplishments include the highly acclaimed miniseries World Without End and the indie movie Weekend, amongst other notable roles.

Other new characters reportedly joining the fold for its fourth season include Dame Harriet Walters as an old friend to Dowager Countess (Maggie Smith), Dame Kiri Te Kanawa as a guest of the home, aristocrat Charles Blake (Julian Ovendon), Green (Nigel Harman), and the Duchess of Yeovil (Joanne David).

"The addition of these characters can only mean more delicious drama, which is what Downton Abbey is all about," Masterpiece executive producer Rebecca Eaton explained in a statement.

Executive producer Gareth Neame added that "Downton Abbey  has seen many great characters visit the house over the years and we couldn't be more thrilled to welcome the new faces that will be joining the regular cast of Downton Abbey in Season 4. We hope audiences will be as excited about them as we are."

In other Downton news, ITV recently released a photo of Lady Mary and baby George, which is the first official peak at Season four. The network gave the following description of it:

"Downton Abbey series four finds Lady Mary mourning her husband Matthew, who dies six months earlier in a tragic car crash. Mary had just visited his wife and new baby George in hospital and was returning to see his family when his car overturned killing the heir to Downton."

The show is set to return at some point in the fall of 2013. Information on the upcoming season will be posted as it continues to unfold.

Tags: Downtown Abbey television