John Slattery. Photo: Jason Merritt/Getty Images

John Slattery likely won’t live down his final scene in last night’s Mad Men season finale any time soon, but, as he told Vulture today, his glorious, LSD-inspired bare-assed moment was a more symbolic expression of the journey Roger Sterling has made this season. And it’s true: Sterling has gone from bullying Pete Campbell to encouraging Don’s comeback, from traumatizing Sally Draper (albeit unknowingly) to seeking a deeper connection with Megan’s mother. Slattery, who both acted and directed again this season, spoke to Vulture about just how realistic our expectations are for Roger and Joan, his feelings on Lane’s departure, and what’s ahead for Roger.

First thing’s first: What is going on with Roger and Joan? They’re finally both single, basically. Why hasn’t he gone for it, when he knows the kid is his? And what exactly does Megan’s mother have over her?

Oooh, probably untrod ground, you know? He’s been with Joan, he knows what that’s like. He’s looking for new experiences, which is probably why he took the LSD to begin with — [he wanted a] life-changing experience, and his life isn’t over by a long shot, and he’s enchanted by Megan’s mother. I don’t know — obviously he and Joan have a connection, but maybe there’s less of an illicit quality to it. They have a kid, he’s trying to support her, and she won’t have it.

I was astounded that he didn’t really stand up for her in the Jaguar transaction. And yet when Lane killed himself, he immediately volunteered to take her home. Please explain.

Well, I mean, I was a little surprised that people were so shocked she would undertake that transaction. She’s done other things — she’s slept with other people before, she’s a sexually confident person, she knows what she’s doing, and this was an opportunity for her to set herself up for the rest of her life. She’s probably undertaken transactions like that for less. I don’t think it was necessarily Roger’s place; if she’s negotiated terms to her satisfaction, then good for her. I think they understand each other, they probably love each other, but it doesn’t mean they have to be together. And from a dramatic standpoint, it might be satisfying for a minute but I don’t think in the long-term — then what do you do? Where do they go? I don’t know. I’m not the one telling the story.

At the beginning of this season, Roger was constantly going off on Pete — and it occurred to me that perhaps he has more in common with him than he’d like to realize. Do you agree?

I think Roger’s come to respect Pete. In the early going, Pete hadn’t really established himself in the office — and despite that, he was always right. If you look back between Kennedy and Nixon or civil rights issues, Pete had his finger on the pulse more often than not, and was shot down maybe because of the way he delivered the message. At this point, maybe Pete has grown into his position, he has more confidence, and he’s bringing in business, and Roger isn’t — maybe through the light of LSD or whatever — interested in beating the crap out of him on a weekly basis. But maybe he also realizes Pete’s bringing in the business, and that means he doesn’t have to.

It seems like Roger is sort of content to sit back and let things happen now.

Well, I don’t know. I would counter that by saying he realizes it’s too soon to quit. I think he’s had this experience and he’s looking for something more meaningful than just arguing with Pete Campbell.

Roger and Don are having parallel life moments at this point in the show, realizing they’re not just immortal playboys, that there’s still something worth trying for in life.

You know, it’s funny you say that, because they’re all in various states of progression along those lines. Pete Campbell has realized everything he has isn’t making him happy; Peggy decides it’s time for her to go out on her own; Joan dumps her husband because she finally hits rock bottom and realizes he’s not the man for her; and Draper’s in this position … they’re all somewhere along that journey. And Roger has realized his marriage isn’t what he wants, his station isn’t making him happy, and he’s taking steps to try to fix it. Everybody’s just trying to figure it out.

Roger’s experience with LSD was a pivotal moment this season. Pretending to be on a trip strikes me as something that could go south super quickly. How did you decide to play it?

We shot one of the scenes, the one in the bathtub, a second time because Matt wanted Roger to be more amused by seeing the World Series; initially we re-shot it because the wallpaper wasn’t what he wanted, and we had the luxury of doing that because we weren’t on the air. And then when we did it, Matt decided he wanted Roger to be more amused by this vision. I bring that up because all the imagery was really specific. My job is to convincingly render that scene as someone who’s looking out into a room and seeing the parking lot of the ball park in Chicago, and some of the other imagery — looking in the mirror and seeing Draper, or looking in the mirror and seeing my hair a different color. There’s a simple reality you’re trying to convey, but all the imagery was very specific. The collapsing cigarette in the vodka bottle with the music coming out of it: They played the music, I took the cap off, and someone on set pressed a button and a loud strain of Russian music was screaming out into the room. You’re given a lot of support; it’s not like you’re standing there having to do this tap dance by yourself.

The episode you directed this season, “Signal 30,” was one of the most broadly pitched of the season, but also one of the most humorous. Did you choose that one, or did Matt give it to you? How does that usually work?

You direct the one you’re given. The schedule plays into it. I was supposed to direct an earlier one, I think, and because I’m in it they have to figure out an arc in terms of the season where I’m light so I can prep my episode and not be so heavy in the one I’m directing. It’s really a time issue; if you direct the scene you’re in, you have to go outside, watch the monitor, then go back in and do another take. If you’re just directing and not acting as much, you don’t have to take time out. It becomes a bit of an issue, but you’re given the script you get. I take what I’m given, and I had a great script — I’m glad I did that one.

Does directing occasionally mean you get secret early script access? Jared Harris insinuated as much to us the other day, when discussing his sad early demise…

No, I mean everyone knows where the scripts are hidden, it’s just a matter of finding the time to go dig one out. Certain people see them earlier because they have to do certain preparations — going to the costume department or hair and makeup — you root around a few days sooner. But I think everyone finally gets wind of it and that event was huge. And it was awful, not only for Lane but for us, because Jared is amazing. We love him. That was heavy. I mean, I hate that he won’t be there. He’s a great actor and presence. Oh my God.

He told us there was always a feeling in the air this season that someone was going, and Roger’s recognition of his own mortality is certainly becoming more front and center. Did you ever fear it was his turn to go?

Well, I mean they wanted to cut characters and expenses and stuff, so there was some discussion of characters, and of course people send you links to sites where they predict it’ll be you. And yeah, it could be anybody. I’m glad it wasn’t me, but I’m sorry it was Jared. I hope I stick around. I mean, any time a character has to go it’s because of story. I’m sure when it’s my turn, there’ll be a reason for it.

Let’s discuss your last scene. For a guy who’s been with so many women, it’s certainly taken a long time for us to see Roger’s ass. Why was now the right time? It seemed like rather symbolic nudity.

It’s funny, I read that [script] and you think, Who wants to be naked in front of a camera? Especially nowadays, when you know it’ll be on someone’s cell phone or around forever. The fact that it was Roger who took the LSD to begin with was surprising, but it made sense, and the end made sense. So as intimidating as it can be to do something like that, it made sense to the story, and Matt never makes a false step. You know you’re in good hands. And sure enough, it worked. It’s a funny scene, but it actually makes sense in a storytelling way. It’s not gratuitous.

The season finale had a much quieter feeling than expected. What did that last scene mean to you, for Roger? Where do you see him going into the next season?

Well, like you said, I think it was symbolic: Roger standing there with no clothes on, arms wide open, staring out at the world is saying, “I’m ready, I’m vulnerable, I’m waiting for the next experience, come what may.” It’s a pretty great place to be. It’s probably scary, which is why he asks Julia [Ormond]’s character to go with him. He says, “I need to do this again, and I don’t want to do it by myself, because I don’t know what’s out there.” But when she says no, he strips down and does it by himself. It’s adventurous and courageous in a way; for someone that age, being brought up the way he was, at this place in his life to say, “I need something new and I don’t know what it’ll be.” Who knows what will happen? I could jump in front of a bus and kill myself, I don’t know. I think it’s pretty astonishing, and I can’t wait to see where he goes.