Dylan McDermott & Dermot Mulroney on Dermot Mulroney & Dylan McDermott

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It was bound to happen eventually. Or maybe not, because this is all a far-reaching conspiracy and these two are totally the same person. Anyway: Dylan McDermott and Dermot Mulroney — once the subject of an SNL game-show sketch, "Dylan McDermott or Dermot Mulroney?" and both former costars of Julia Roberts — will share a screen and act opposite each other in it! Mulroney will guest-star in multiple episodes of Fox's new airplane-set comedy LA to Vegas as a rival alpha pilot to McDermott's Captain Dave. (Their first showdown is scheduled to arrive at 9 p.m. ET/PT on Jan. 16.) Here, the 56-year-old McDermott and the 54-year-old Mulroney — whose credits include The Practice, Young Guns, In the Line of Fire, and My Best Friend's Wedding; we'll let you sort out which belong to who — play more than the name game.

Can you recall the first time you heard about… the other guy?

DYLAN McDERMOTT: I was at William Morris [Agency], where I think you were originally. Is that right, Dermot?

DERMOT MULRONEY: Yes, that's right.

McDERMOTT: I remember Sue Mengers coming up to me in the hallway, saying, "There can't be two of you. There can only be one. One of you is going to have to change your name." So I've been waiting for 30 years for Dermot to change his name. [Laughs.]

MULRONEY: We've never had this conversation, Dylan. There was a moment while I was represented at that agency where that came up. I gave it some thought. I really did. Naturally, it made sense for me to use the last name McDermott, because Dermot's in that last name. The first name Dermot that I would be relinquishing by changing the name. I just slipped it into the last name, McDermott, the one that you have.

McDERMOTT: So you were going to be Dermot McDermot?

MULRONEY: No — I was going to go by Matthew McDermot. Matthew was my confirmation name.

McDERMOTT: Hey, get this! I was also going to do it. You know what my name was going to be?

MULRONEY: What?

McDERMOTT: Mick Dermot.

MULRONEY: Oh, I'm so glad you didn't do that. That would have been so confusing!

McDERMOTT: Yeah, right — like the 30 years haven't been. [Laughs.]

Had you two crossed paths much over the years?

MULRONEY: Very infrequently. We've compared some notes when we worked together just now, but it's in the threes or fours.

McDERMOTT: I'd say the greatest meeting of all time was when we were both naked in the Beverly Hot Springs, and we ran into each other.

What?!

McDERMOTT: How about that one for folklore? What was your recollection on that, Dermot?

MULRONEY: My recollection is as it has been ever since: What the f— am I doing in Beverly Hot Springs? [McDermott laughs.] I went running for the hills and never went back, Dylan. When you called me for the part in LA to Vegas, it called that back. I hope you enjoyed all those body scrubs that I missed, all because of the traumatic meeting at the men's spa.

McDERMOTT: We've probably seen each other, like Dermot said, three or four times. But the fact that we would run into each other naked at Beverly Hot Springs, I just thought was poetic, because what are the chances? It's really been a journey all these years to finally get comfortable with each other because you're mad at each other that you have the similar name, people are confusing you. It's like two countries that have been at war for 30 years finally call a truce. And finally realize we actually like each other.

MULRONEY: We can get along peacefully and share a border.

Did that naked situation offer more clarity or less clarity that there was a difference between you two?

McDERMOTT: Well, for me, it was more clarity. Absolutely. I'll leave it at that.

MULRONEY: Let's just say: Now, at least we know how to tell us apart.

Were you nervous that this joining of forces might not live up to the hype, that maybe it was best left as what-if legend?

McDERMOTT: When [LA to Vegas creator] Lon Zimmet called me and said he wanted Dermot for the role, I said, "I think that's the greatest idea I've ever heard in my life." So I was gung-ho, I was all for it. I thought it was just genius. Forget about the names — Dermot is a tremendous actor, and he kills Captain Steve. I was just so happy that he wanted to do it because he could've just shied away from it and said, "No, I don't want to it." The fact that we both wanted it so badly was miraculous.

MULRONEY: Dylan and the comedic genius producers he's working with, they really called my bluff. There was no way for me to pass, because then I would've been the one who didn't look him in the eye. I took it on as a privilege and a challenge.

How do we know this is true that you two are actually playing opposite each other and it's not one of you just playing opposite for yourself à la Tatiana Maslany in Orphan Black?

McDERMOTT: I don't think that question will ever be answered. The bigger question is: Will it end the confusion between us?

MULRONEY: It's been so rewarding. We feel that each of us alone would be but one. This way, we are like one bigger confusing mess, but we are one together.

McDERMOTT: We don't want to put it to bed. We want the confusion to last forever. And, get this: They're finally paying us for it.

MULRONEY: Mine's just like a modest guest-starring type of fee, but at least one of us is cashing in on this 30-year buildup, you know? Here's to you, pal, way to go! I'm all for it.

McDERMOTT: Thank you, brother.

What did you feel on that first day of filming? A disturbance in the force? Did the camera start malfunctioning and the lights flicker for a second?

McDERMOTT: I saw him, and I think we just hugged each other because it called for that. [Mulroney laughs.] It just called for two men with similar names to hug and finally to work together… What was really great is that the script lent itself to real life. There was this rivalry that's happened for so long, and then the script kind of reflected that, And he looked so great too. He had a mustache just like mine.

MULRONEY: They had called me in advance and asked me to bring in a real mustache, so I did my best to do my best Dylan McDermott. Which is more or less what I've been doing all along.

McDERMOTT: And so have I been doing. [They laugh.]

MULRONEY: It felt pretty monumental, to be honest.

And the hug was good for you, Dermot?

MULRONEY: The hug was good. You know, he's a broad-shouldered man. He's a little taller. I always try to really hug up to tall guys, because I respect them. So I gave him the best manliest, broad-shouldered hug I could give back.

NEXT: McDermott and Mulroney on whether they've ever blamed a bad project on the other guy

Captain Steve seems to push all of Captain Dave's buttons. How would you sum up this rivalry?

McDERMOTT: Captain Steve is everything Captain Dave wants to be. He has international routes, and that's all Captain Dave ever wanted from life. Now he's on the puddle jumper. He's declined over time. He probably started at American and went to United and now he's on Jackpot. Here comes Captain Steve, who was flying international. Everybody loves him. So for Captain Dave, it's salt in his wounds.

MULRONEY: And like our newfound friendship on a long acquaintanceship, these guys go way back. They mention that I had a lot better scores in the flying school and better luck with the ladies. I think Captain Steve is pretty much universally considered a superior person in every way. So it mirrors reality in that way as well. [McDermott laughs.] No, we had a blast.

Is the cockpit door open for many more episodes?

McDERMOTT: Captain Steve does come back. At least for another episode. The rivalry deepens. I will tell you that they get into a fight. Even bigger than the first fight. This second fight is even more epic.

MULRONEY: Epic and profound.

If you could steal one credit from the other person's resume, which would it be and why? Or maybe you've already taken credit for it?

MULRONEY: I think Dylan wants to be Captain Steve, and I want to be Captain Dave.

McDERMOTT: I would say for me it would be Young Guns… He was a badass in that movie. I love Westerns. I would have liked to have been in that movie. I thought he did a great job and definitely would like to put that on my resume.

MULRONEY: So nice of you to say so, Dylan. I remember when you were cast in In the Line of Fire with Clint Eastwood. I thought that was a really great turn on your part.

McDERMOTT: Thank you, brother. That was a fun one.

MULRONEY: I saw that one and could have played in that role too. Sometimes you spot those parts. I always like it when the other guy does such a nice job in them.

Have you ever blamed a bad project on the other guy?

McDERMOTT: I've definitely blamed Dermot for maybe five or six bad movies I've done.

MULRONEY: [Laughs] Gives me a bigger footprint… I frequently sign Dylan's name on autographs.

McDERMOTT: Even further confusion was, we had the same manager for a time. How she juggled us, I'll never know.

MULRONEY: Imagine being that new assistant on the desk.

McDERMOTT: As a matter of fact, I think you did a movie with Sam Shepard, right, Dermot?

MULRONEY: Yeah.

McDERMOTT: I did a movie with him, Steel Magnolias, but after that or before that, but I got a call from my agency saying that Sam Shepard wanted to talk to me about a movie. But actually, he was looking for Dermot, not me.

MULRONEY: Ooh. That one stings.

McDERMOTT: Yeah. That hurt.

MULRONEY: I worked with him a number of times. Dylan, sorry about that. Whooh.

McDERMOTT: That's okay. I had the pleasure of working with him, too. He was a great one.

MULRONEY: Indeed. One of the greats. I had one that stung a little bit. I don't think Dylan plays any musical instruments. Do you, Dylan?

McDERMOTT: No, I don't.

MULRONEY: I play a sh–load of them. One time I was asked to perform with Edward Sharpe of the Magnetic Zeros. At the Hollywood Bowl! I learned the song. I rush out, joined that kind of Boheme shanty band they have. Amazing, amazing high point in my career. And as I'm leaving the stage after that song, the girls are screaming, "Dylan! Dylan!" And I thought, "Aw now, come on! Really?" How else do you individuate? So, that was one for me where I thought, "See? I can't even get that right."

McDERMOTT: [Laughs.] Well, I'll go one further on that one. I was at a charity event with my fianceé—

MULRONEY: I'm cringing so bad right now, man.

McDERMOTT: The host says, "And also here tonight is the lovely Maggie Q and her fiancé, Dermot Mulroney."

MULRONEY: Oh goodness.

McDERMOTT: So, you see? No matter how deep you go, it goes deeper and deeper and deeper every time!

Dermot, I feel like we need to talk about the movie Staying Together.

MULRONEY: Yeah, we do need to talk about that.

What did that do to your brain to play a character named Kit McDermott?

MULRONEY: To your earlier questions, I believe it was during that that I learned that there was an actor Dylan McDermott. So, it's worse than you think.

Are you saying that that wasn't a wink?

MULRONEY: No. That script existed. It was considered a fantastic script. Actors Studio director Lee Grant wrote it. It was a sought-after role. Dylan, did you audition for that?

McDERMOTT: I can't remember… Our friend who recently passed away, Tim Quill, was in that movie. I had done Hamburger Hill with him, so it must have been after Hamburger Hill.

MULRONEY: You did Hamburger Hill after, which I auditioned for. Pour some out for Tim Quill, that's for sure. So I learned after I'm cast in a role to play a guy who has a last name that contains my first name within, during that process, I learn that there's an actor named Dylan McDermott who's in that same age range. You couldn't Google the guy. I didn't know what he looked like. You'd have to run over and you'd have to pull a copy of Players Directory off of the shelf. You remember this, don't you, Dylan?

McDERMOTT: Oh my god. That's right.

MULRONEY: There was a little Facebook encyclopedia that was like the golden book of head shots. You had to pay $35 a year to get your picture.

McDERMOTT: That's like the Thomas Guide. I forgot all about it.

MULRONEY:. It's the Thomas Guide of actors. Leading men, character actors, young ingenues…

Speaking of leading women…. Dylan, you played Julia Roberts' husband in Steel Magnolias and Dermot, you played her best friend in My Best Friend's Wedding. Is she aware what happened, or does she still that believe she was reuniting with Dylan for My Best Friend's Wedding?

MULRONEY: Yeah, that was a real process. I went in and auditioned. Then I pulled off my Dylan McDermott mask from just below my chin and I got the part.

McDERMOTT: And he was great in it. They were both great in that movie. That movie became really a calling card for Dermot in many ways. I was talking to my fiancee about that the other night. She told me that everybody was in love with Dermot after that movie, and I think that's accurate.

MULRONEY: It was a great film to be in. It's become a classic. And let's not forget, Julia went on to marry a DM. There's further evidence. Make of it what you will.

Would you guys consider yourselves a slightly more modern-day Bill Pullman/Bill Paxton?

McDERMOTT: Don't forget, we were immortalized on SNL. Let them have that first because the confusion is much deeper for us than it is for anybody.

MULRONEY: And more profound.

McDERMOTT: What we did too on set, also which I thought was fun, when the director would give Dermot [instructions] and say, "Hey, Dermot. Would you do this?," I would answer.

MULRONEY: It seemed to work every time. It was just a real dependable gag. Real go-to stuff.

I also picture the director calling "Cut!" and both of you sitting in the same director's chair at the same time.

MULRONEY: They didn't have a director's chair for me, man. But we did visit that other set. That was pretty confusing for people.

McDERMOTT: Oh, that's right. Dermot and I went over to the set of The Mick.

MULRONEY: We were similarly dressed as pilots.

McDERMOTT: We walked over there together as they were doing a take, and we walked on the stage together. You want to talk about confusion — those people's heads were blown off their shoulders. They didn't know what to do. I mean, the music turned off. There was silence for like five minutes — they just looked at us.

MULRONEY: They looked at us with respect.

McDERMOTT: I think that's what it was.

At the end of the SNL bit, which you were in, Dermot, Bill Hader says the next round is going to be three teenage girls from Alaska playing "Djimon Hounsou or Chiwetel Ejiofor?" How would you do?

MULRONEY: Yeah. That's easy. No confusion. No problem. Chiwetel Ejiofor, what's the big deal? Different category. Next.

McDERMOTT: It's the syllables in our name.

MULRONEY: Don't forget the letters. It's similar letters.

McDERMOTT: The letters, the syllables, the Irish. There's so many things going. Roughly the same age. [To Mulroney] Dylan… I mean, Dermot. I called him Dylan. You see that?

MULRONEY: Good god.

Did that just happen?

McDERMOTT: That just happened. I called him Dylan. Even I'm confused now. You confused me.

MULRONEY: What I experienced was just like a relinquishing. It wasn't giving up. It's not the same thing. It's more like giving over to. That's what happened for me in that moment, but I've never made that mistake. But for the record, people mistakenly refer to me as Dylan much more frequently than people mistakenly refer to Dylan as Dermot by first name. It happens to me more often that they use the wrong first name. Because I, like Chiwetel Ejiofor — now that's a category. We both have weird names. So we're in that, but Dylan isn't. So I have a whole other name category that I don't think [Dylan] does. I don't think he qualifies for weird name because Dylan McDermott is just like it's spelled, and you can figure it out when you see it. Mine doesn't have that luxury…

McDERMOTT: I guess the big question is whoever passes away first, will that be in our obituary? Or in both of our obituaries.

MULRONEY: Here's to you pal, I'm going to make an advance request to the New York Times.

McDERMOTT: To the bitter end!

Was the SNL sketch the moment when both of you knew that this Dermot/McDermott thing had moved beyond a little fun thing into cultural phenomenon?

McDERMOTT: Absolutely… My Instagram was McDillet for about a year or so.

MULRONEY: It went viral differently in that age. Every year is like a different era. It had its own space, for sure. I didn't know what was happening.

McDERMOTT: It's almost beyond that.

MULRONEY: Now I've given over to it, and I'm not thinking correctly. I've got to go back to somehow resisting it ever so slightly. Then I'd be more authentic and more myself again. So I've also come full circle within the full circle that we have come.

Is there another person you'd like to bring into the mix to make this more confusing? Dylan Walsh or Dean McDermott?

McDERMOTT: I think it stops with him and I. It's a couplet.

MULRONEY: I've tried to make it happen elsewhere, and it's just not the same. I palled up with Chris Meloni for a little while. I thought that was going to happen. No purchase. It didn't get any traction. So, like it or lump it, this is how we do.

LA to Vegas airs Tuesdays on Fox.