It’s been almost two years since Dan Stevens’ beloved “Downton Abbey” character, Matthew Crawley, met with an untimely end, and some die-hard fans of the PBS costume drama still may not quite be over it. But for the 31-year-old British actor, Crawley’s tragic death marked a kind of rebirth - or at least a chance to strike out in some very different directions as an actor.

Stevens, who costarred with Jessica Chastain in last year’s Broadway production of “The Heiress,” stars in two films opening this week, playing characters who would never be mistaken for the kind, noble Crawley. In the thriller “The Guest,” in theaters Sept. 17, Stevens is a steely-eyed, possibly homicidal American soldier who upends the lives of a family when he mysteriously shows up on their doorstep. In the crime drama “A Walk Among the Tombstones,” opening today, he stars opposite Liam Neeson as a hardened New York drug trafficker seeking vengeance against the men who kidnapped and murdered his wife.

When you were doing “Downton,” you said you sometimes felt like Matthew Crawley was “too gentle.” Were you looking for a way to explode any notion of typecasting you as “slightly repressed period English guy”?

Well, there was no guarantee that it would explode anything, but from a personal artistic sense, it just felt good to explore some other avenues. I guess part of the appeal of (“Downton”) was that you had this sort of milquetoast guy with this very strong woman by his side. It’s been fun the last couple of years getting to expand that range a bit. That’s all I’ve ever dreamed of, really, is that opportunity to just try another accent or put on another suit and see how it feels.

“Downton” fans were shocked by your sudden exit from the show at the end of the third season, and some seemed to feel a bit betrayed. Were you surprised by how intense the reaction was?

I guess I was. In a funny way, it was a curious compliment to the character that people missed him so much and couldn’t bear to see him go. What’s been heartening recently is that now people are starting to see a few of the things that I’ve been up to since and are beginning to understand the desire to go try different things.

For “The Guest,” you had to transform yourself physically into a buff special-ops soldier. How did you pull that off?

It was a great challenge. I trained seven days a week, four hours a day with a guy who had previously been a world taekwondo champion. It was a lot of circuits, weights, martial arts - basically just not stopping at the point where I normally would stop, the point where it hurts.

On top of acting, you studied literature at Cambridge, you co-founded a literary journal, you’ve been a columnist for the Daily Telegraph newspaper, and you play the violin and cricket. Have you always been this annoyingly well-rounded?

Well, I don’t play the violin very well, and I don’t play cricket well at all. But I just like challenging myself in new ways. Now I’m trying to focus that more toward my acting, so that each role has a different element to it.

What’s been your most surreal encounter with someone you admired who turned out to be a “Downton” fan?

Ben Stiller. One night when we were shooting (“Night at the Museum”), he was like, “I really have to ask you some ‘Downton’ questions.” I said, “OK, as long as I’m allowed to ask you some ‘Zoolander’ questions.” We still challenge each other back and forth with “Downton” questions on the (mobile game) QuizUp. He has an encyclopedic knowledge of the show. But he has yet to beat me.