Credit: Ian Gavan / Getty Images For The BFI

Tall, dark, and handsome — that’s the easiest way to describe the newest dreamboat docked at Downton Abbey. Welsh actor Tom Cullen joins the crew for Season 4 and boy, are we glad.

As much as we treasure our three years with Matthew Crawley (Dan Stevens), Lord Gillingham as played by Tom has done a lot to help us through the stages of grief. And the same proves true for his onscreen love interest and Matthew’s widow, Lady Mary (Michelle Dockery).

Credit: Tom Cullen on Instagram

So what about off camera? Is Tom single and ready to mingle? Prepare the tissues, dear readers, because unfortunately for us: Tom’s got a girlfriend.

The lucky lady is Tatiana Maslany, a Canadian actress best-known for playing the lead on sci-fi thriller Orphan Black.

The pair of hot 28-year-olds have been dating since at least September 2012; the duo walked the red carpet together at the 2012 Toronto International Film Festival and, more recently, shared a sweet photo in the snow that reminded us of another wintery romance played out on Downton

Tom and Tatiana haven’t publically confirmed how they met, but based on their IMDB profiles, we’re guessing they fell for one another on the set of World Without EndThe 2012 TV mini-series is set during the 1300s and, funny enough, Tatiana played a nun! Guess we’ll be buying a habit if that’s what catches the eye of a stud like Tom Cullen.

Sources: Tom Cullen on IMDBTatiana Maslany on IMDB

Elisabeth Kramer is an Assistant Editor at Wetpaint Entertainment and our resident Downton Abbey expert. Follow her on Twitter and Google+!