Judging from the instant chemistry between John Slattery and Allison Janney, it’s hard to believe the two longtime actors had never worked together before. The silver-haired star of “Mad Men” and the Emmy-winning actress — now doing double duty on “Mom” and “Masters of Sex” — started chatting from the moment they arrived for their photo shoot on the CBS lot in Studio City. They realized they’ve both been lucky enough to have had dream roles — but also had to endure more than their fair share of onscreen nudity.

Variety: John, are you ready to say goodbye to “Mad Men”?
John Slattery: It’s been seven years but by the time it finishes airing it will have been almost 10 years between shooting the pilot, waiting for it to go and then whatever irregular intervals. My son was 6 (when it started), and he’ll be 16 when it finishes.
Allison Janney: Mine was seven years (for “West Wing”). You try to prepare yourself for it ending, and you will feel the loss of it.
Slattery: That’s what I think, and I don’t know if I’m ready. You don’t start out in this business thinking, “I’m gonna get one great part and play it forever.”
Janney: Because it’s so rare to have steady work as an actor, isn’t it? It’s such a luxury and it feels like “Gosh I could really get used to this. This is lovely.” And then it ends and you’re back to … ugh.

Variety: John, you’ve just directed a movie. What is it about going behind the camera that appeals to you?
Slattery: Telling people like her what to do. (Laughs.) We all have opinions. I mean, I’m standing around sets long enough and you kind of go, “Well, I wonder what it would be like to do that.” You think, “If I was doing it maybe I’d try that” or you ask questions and you know it’s someone else’s vision.
Janney: I’m so glad I don’t have to do that.
Slattery: It’s a lot to bite off, but I wanted to give it a shot. “Mad Men” seemed like such a good place to try because everybody is so good at their job. The writing, the material is so good and you know everybody.

Variety: Allison, you have no interest in directing?
Janney: No, I would make a terrible director. I’m not good at communicating verbally. I think I would not know how to get an actor to do what I wanted him to do. I had a small fantasy about directing a play to get my feet wet. I just love working with directors who know what they’re doing. I feel like they’re doing what they’re meant to do, and I’m doing what I’m meant to do at this point.

Variety: What makes for a good supporting actor?
Janney: Make everyone else around you look really good.
Slattery: Have selflessness, lack of ego, team players. Capital T.
Janney: I’ve only been No. 1 on the call sheet once, and I think I had to tell myself I was No. 12. I wasn’t comfortable. I was like, “Actually, bury me a little bit.” I’m better buried. I’ll come in and knock it out of the park.
Slattery: Be careful what you wish for. No 1 on the call sheet wishing you were No. 12? Can we switch places?

Variety: What attracts you to a role?
Janney: The writing’s what first gets me, and then the development of the character and where it goes and what I can do. Could I do that? Does it scare me? And who’s directing it and who’s in it and what I get to play with.
Slattery: The bottom line is it has to be on the page. It has to be the part that you go, “Oh I have to do this.” It’s not even like, “Do I want to?” The whole thing lines up where you’re just thinking, “Well, I have no choice. I have to do this.”

Variety: Did you feel that from the beginning with “Mad Men”?
Slattery: The beginning of “Mad Men” was a weird start. I auditioned for the role of Don Draper because my character wasn’t evident so much in the pilot, so they kind of pulled one over on me a little bit. But it wasn’t long before I got the scripts and went, “This is better than the last one,” and they kept getting really good. Sometimes the pilot will be great and you start to crank out shows a week at a time and the quality drops because of the time factor. This was kind of the opposite. They just kept getting better and better.

Variety: Allison, what about “Mom”?
Janney: I had been looking for a half-hour comedy. It’s the one format and genre that I hadn’t really done before, and it appealed to me because of the schedule and working in front of a live audience. I thought that was a perfect amalgamation of all the different ways I’ve worked. It sounded like a good fit for me. I knew Chuck (Lorre) was doing it, and I’d wanted to work with him before. I had gone to see a psychic right after “West Wing” and she said you’re going to do something big with “CL.” I did this development deal with him and it didn’t go, and I was like, “She was wrong! I hate psychics!” And then (“Mom” came along and) I was like, “She was right!” but that’s not why I jumped in. It was because of Chuck, and the pilot was funny, and I love Anna. She’s a delightful, perfect co-star for me. She has the same sort of work ethic that I do and is nice and treats everyone well. I just like to be on sets where people are nice to each other and respectful of what everyone does. And Bonnie with the backdrop of her alcoholism and recovery — I’ve dealt with that in my life with my family and friends and felt very comfortable portraying a woman who is dealing with that. I am a recoveree myself.
And with “Masters of Sex,” I got a phone call from Michelle Ashford and Sarah Timberman, and I thought these are the kind of people I want to play with as an actor. I was a little afraid of doing the nudity but it’s just so funny. Things have always come to me late in life. I’ve been a late bloomer for everything. My career didn’t start until I was 38. I’m getting offered sex scenes at 50. Seriously? I guess I’m in better shape now than I was in my 20s so let’s do it and just pray that the d.p., Michael Weaver, lights me well and my mom and dad are doing something else at that time.

Variety: How do you handle the nudity?
Slattery: I have to have lots of nudity riders in my contract. Very specific. What side, what part. They have it so explicit. What can we see, what can’t we see, and how long can we see it? You know like really? That’s what you want to see?
Janney: I thought just sign a general one, and I trusted the creators of the show that they were going to be respectful of me and what I felt comfortable with. I had no doubt that they were not going to take advantage of me in that way. And they were wonderful. Am I going to watch it? No. Will I watch it when I’m 75? Yes.
Slattery: That’s the thing you’re always like, “Ugh, I look so old,” and then 20 years down the line you’re like, “What was I so worried about?”

Variety: How much creative input do you have in the direction of your characters?
Slattery: Zilch. I don’t know about you, but I have none.
Janney: None, and I’m OK with that. I’m not a writer. I don’t have a writer’s mind. There are certain things I would love to have, different people I’d like to bring on the show. Jeez, it would be great to have John Slattery on the show as my boyfriend. Could we work that out?
Slattery: We’ve both done nudity. It would be like 10 minutes and we’d be finished.
Janney: I wish there was a suggestion box where we could put it in and the writers wouldn’t know who it had come from. I would like to have my character come back more on “Masters of Sex.” I think she should be a sex therapist now, but I would never go up to the writers and ask them to do that for me.
Slattery: You just did.
Janney: I just did!

Variety: Do you prefer comedy or drama?
Janney: Both of my shows incorporate both. With “Masters of Sex” there have been a lot of touching scenes, really heartbreaking scenes, and yet there’s comedy within that. I find it amazing and heartbreaking when the hooker asks, “What’s your husband into?” And she says, “Well, he loves Salisbury steak and the opera.” I’m not going to play it for the laugh, but I love that. Then “Mom” having a huge monologue about why I drink and how I came from the foster care system and how painful her life was and allowing her to become emotional — and then going, “Yeah, but I stole the TV on the way out.” It feels very messy and very real.

Variety: John, certainly Roger brings the comedy to the drama on “Mad Men.”
Slattery: Yeah, I feel like I’m in a comedy most of the time, but then writing like you just mentioned, where you do a scene that’s extremely heartfelt and then you have a zinger at the end — that’s really the writing. It’s such a pleasure to play that. Just when you think he’s one kind of person — just someone who comes in and says something funny and smokes a cigarette and leaves, all of a sudden there’s another side of him. He has a certain set of loyalties or feels extremely strongly about his experiences in World War II or his first wife, and with this thing kind of winding up, it’s somehow getting elevated. Maybe it’s just the fact that we know that the show is coming to the end, so everything seems a little more vivid.

Variety: It’s often said we’re living in a golden age of television. But do you feel that? Do you feel that you’ll always get work this good?
Janney: The advent of reality TV I just thought was going to kill TV. I just saw the end of television, the end of good writing and good acting. I’m really disheartened by it, and it’s still there and it’s huge. I guess it has its place. I always feel that’s what caused the demise of “West Wing,” and we lost a lot of viewers to “The Bachelor.” I just got mad at this country for rubbernecking. Why are people doing this?
Slattery: It’s not called reality TV anymore. It’s called unscripted because it isn’t real, because they pay people to chase a guy. I know why they do it. The economics of it are they make a lot of money doing it, and people like it. I guess it’s escapist somehow.

Variety: Did you always know you wanted to be an actor?
Janney: My mom was an actress so that seemed like a really romantic thing to do. As a young girl, it made an impression on me. She would take us to different towns to see her friend Eileen Brennan perform in plays. I just worshipped her. But I didn’t know it would happen for me. I was too impossibly tall to be cast in anything. I was always cast as a 40-year-old woman when I was 22. But there was nothing else I could do, believe me I tried.
Slattery: I was an excellent waiter. The worst. Someone told me with a big smile on his face, “You know, I’ve been working here for 15 years, and you are the worst waiter I’ve ever seen.” I had just given the wrong bill to two different tables.

Variety: What’s your favorite role you’ve ever played?
Janney: Obviously, C.J. Cregg changed my life. It was a great character to play, but unfortunate to live up after in terms of people thinking that’s who I am. No, I don’t enjoy talking about politics.
Slattery: Do you know more about politics now than you did then?
Janney: Yeah.
Slattery: ’Cause I don’t know anything about advertising. I don’t know shit about advertising. I don’t think anyone on “Mad Men” knows either.

Variety: Is there a question you’ve always wanted to ask each other?
Janney: Why haven’t we worked together?
Slattery: That’s a good question. That would be great. We’ve worked with a lot of mutual friends. We’d be a good team.
Janney: So you write it.