By NEAL JUSTIN

The British are staying! The British are staying! One of the most interesting, and welcome, developments in the fourth season of Mad Men, which starts Sunday, is that Lane Pryce, the foreigner who appeared last season as a rotten olive in the advertising firm’s martini, has partnered with his former nemeses to form an upstart group that must prove themselves all over again.

The same needn’t be said for Jared Harris, who plays Pryce. Instead of coasting on the name of his famous father, Richard Harris, the actor has been celebrated for his Shakespearean work on stage as well as his diverse characters in more than 40 films, including The Curious Case of Benjamin Button, Happiness and Natural Born Killers.

Harris spoke to us last week about Mad Men creator Matthew Weiner’s style, his character’s distinctive glasses and whether or not Don Draper and Richard Harris would have enjoyed happy hour together:

Q. Now that you’re a series regular, you’re going to be playing the same character over a lengthy period of time. How is that different than playing the same character time and again on stage?

A. The most different thing is that, in a play, you have the whole of the character in front of you. You know the beginning, the middle and the end. You frame your performance along those lines. In Mad Men, we’re not privy to that. In a way, it’s a different discipline. You can rationalize it, I suppose, by saying nobody knows what their future is.

Q. That’s particularly true with your character. The viewer’s initial reaction was that he was going to be a heavy.

A. That was mine, too. In my first scenes, I’m playing two characters off each other, offering them the same position. Those are the only scenes I saw and I thought I was setting up a deliberate ruse. Well, in the audition, I didn’t do a very good job. Matthew explained that he wasn’t that guy, that he’s actually being told what to do by the bosses back in England and he’s just doing what he’s told. That gave me a whole different context and when I did it again, I got it.

Q. I know that on Weiner’s set, the script is gospel. I wonder if Shakespearean training helped you prepare for that.

A. Absolutely. Last year, I had a bet with (co-star) Charles Shaughnessy to see if either of us could get an improvised word or line into the script. I think he got a “hear, hear” in. The difference is that everyone knows what Shakespeare wrote and you have a month to prepare. On stage, you can focus on paying attention to the other person, really listening, being alive in the moment. With Mad Men, it’s difficult because you don’t have that much time under your belt. You’re drilling the words into your head like a parade-ground sergeant and firing them at other people. It’s a challenge. The people who have been on the show a long time are wonderful at it.

Q. When I think about Lane, I think about his glasses. They seem to say so much about him, but I’m not sure what.

A. That’s one of those funny things. Literally 45 seconds before I did my first shot, Matthew was sticking all these different glasses on, and when these ones were selected, he said they were perfect. They’re sort of obtrusive, those glasses, a barrier between the character and the viewer. Of course, they can be quite difficult for the cinematographer, because they’re quite small and it’s tough to see somebody’s eyes, which you want to when you’re in closeup. They help you figure out what the character is thinking.

Q. Do you ever catch your father’s influence in your performance?

A. I think it’s inevitable. I mean, you learn your behavior from your parents. I drew on him more than in any other role when I did The Riches, because I was playing a charismatic, unpredictable, dangerous Irish man.

Q. Do you think your father would have enjoyed drinking with the Don Draper character?

A. That’s a tough one. If you told good stories, he would love your company. Of course, he enjoyed drinking with anybody.