Unless you view its portrayal of fundamentalist Mormon polygamists in Utah as a metaphor for all misunderstood alternative families, gay content has been somewhat slim on HBO’s Big Love — especially considering the show’s creators and executive producers, Will Scheffer and Mark V. Olsen, are life partners. But that’s about to change in season 4, which premieres Sunday, January 10, when Alby Grant finally gets a boyfriend. Having long struggled with his sexuality in secret, the power-hungry son of murdered prophet Roman Grant develops feelings for Dale Tomasson, a state-appointed trustee for the United Effort Brotherhood who’s battling his own gay demons in a reparative therapy group. Ross, a 40-year-old steadily working straight actor who also played gay in American Psycho, kisses and tells all to Advocate.com.

Advocate.com: Will Scheffer and Mark V. Olsen, the creators and executive producers of Big Love, have praised your “career-defining” performance in the show’s upcoming fourth season. How are you feeling about the buzz?
Matt Ross: It’s very exciting. This season was challenging because I got to explore a part of Alby I’d never explored before, and it felt very unusual. People will see an Alby they haven’t seen before, which is what I’m most excited about.

Did you know when first accepting the role that Alby would be struggling with his sexuality?
I actually did not know. In the pilot I only have, like, six lines, and I’m just sort of the son and right-hand man of Roman Grant. Really, up until the seventh episode, it wasn’t clear who Alby was at all. Mark and Will had sort of pitched to me who Alby might become, so I had this idea about him, but it was never on the page. Frankly, all I did for most of the first season was just lurk in the background, tremble in fear, and say, “Yes, Papa,” and “No, Papa.” But in the seventh episode, Alby’s sent by Roman on an errand into the city and picks up a male hustler. Even at that point and in that scene, I didn’t know if Alby was gay or not. I still hadn’t talked to Mark or Will about it, so I sort of answered it for myself that he was one of those isolated people who’s so dead inside that he puts himself in dangerous circumstances — like picking up a stranger — in an effort to feel something.

So when did you realize that Alby was gay?
It wasn’t until the following season, when Alby was in a police station, secretly implicating his father, that it said in the stage directions that “Alby is checking out the cops’ butts.” So at that point I was like, “OK, well, now it’s pretty clear he has some sort of homosexual longing.” I still hadn’t discussed it with Mark and Will, but that’s when I realized what that scene with the hustler had been about. Then there was an attempted tryst in a truck stop bathroom in the third season, and by then it was really clear, but it was still unclear whether or not he had ever acted on those feelings.