Dermot Mulroney on playing the Secret Invasion president (and playing cello on the Spider-Man score)

Secret Invasion is a show about power, intrigue, and secrets that go all the way to the top. And in this Marvel Disney+ series, the top means U.S. President Ritson, played by Dermot Mulroney.

Ritson is a key player in the shadowy spy series, crossing paths with Samuel L. Jackson's Nick Fury and forging a (seemingly) close alliance with Don Cheadle's Rhodey. Four episodes in, the show has woven a tangled web of secret plots and shape-shifting Skrulls. One of the Skrulls' key plots centers on President Ritson, and the infiltrators hope that by attacking the U.S. commander-in-chief, they can destabilize human politics worldwide.

EW recently caught up with Mulroney, who opened up about the joys of playing Marvel's POTUS — as well as his surprising musical connection to another Marvel screen project.

MARVEL Dermot Mulroney as President Kitson in 'Secret Invasion'

ENTERTAINMENT WEEKLY: What was it like when you got the call about joining Secret Invasion? Did it feel like you had been elected president?

DERMOT MULRONEY: [Laughs] It's exactly that. I did feel an extra sense of thrill to be playing the president. But there were so many other wonderful things about it. I would be working with Samuel L. Jackson, Don Cheadle, this great cast… I was just thrilled.

Is there a secret to giving a presidential performance?

Well, I'll tell you this: I read somewhere that Theodore Roosevelt got a haircut every day. A barber was one of his main confidantes while he was president, so there was a barbershop in the White House. So I did ask for a lot of haircuts. Mostly it was just one of those continuity things. But they obliged, and maybe that gave me an extra presidential feel.

The most recent episode has a big action scene, where the Skrulls attack the presidential motorcade. You spend a lot of time hanging upside down in a car. What do you remember most about filming that scene?

The whole thing's unforgettable, just to know I'm walking into the middle of mayhem. I was asked not only to get inside of this inverted SUV, but they sort of strapped me into it, so I'm hanging from the seatbelt upside down. It's a really exciting, high-intensity action sequence that you won't find in a lot of TV shows. I know what [director Ali Selim] and the rest of this incredible production have done — the stunt team, the choreographers, the drivers, the special effects, the makeup effects. It's an incredible collection of expert technicians, and I think it's going to stand the test of time, even in the Marvel action world. I think that sequence is going to be remembered.

Tell us a little bit about working with Don Cheadle. I love some of the back-and-forth between the president and Rhodey.

Our director gave us a little room in there to have fun. Man, did we have some laughs. I've been a friend and a fan of Don's for years and years and years. I'm glad that vibe came across in our scenes, and it's important because they've been colleagues working in the White House for a number of years. Although I wish someone would tell me how many years I have left in my term. [Laughs] We'll see if I can make it through to maybe one other series before they roll over to some other president.

I know in addition to acting, you're also an accomplished cellist. You've played on some really impressive film scores composed by Michael Giacchino — including some Marvel projects.

I think the only Marvel score I did was one of the [Tom Holland] Spider-Man movies with Giacchino. I don't know if there's actually a real list of the scores that I played on. Some of them are obscure, and some of them would be big movies that anyone would know. I mean, I'm at the back of the cello section, joining in with incredible, world-class players. [Laughs] But I have had the most remarkable, unforgettable days seeing parts of the completed movie and working with a conductor and a full orchestra, playing brand-new music that in a lot of cases, no one will ever play again. Sometimes with Michael Giacchino scores, they'll be performed again by symphony orchestras. But mainly I like thinking that it's a one-off. I mean, Beethoven's good and all that, but we've been playing the same thing for hundreds of years. [Laughs] So it's kind of nice to know that I'll be just one of the few cellists that ever touched a score.

This might be a hard question, but do you have a particular favorite score you've played on?

I did several Planet of the Apes [movies], and the percussion on that is unbelievable. The implements they used to make some of those sounds on a full scoring stage was fascinating. Coco, that's such a famous score. And Incredibles 2 is great, but that's mainly big band horns, so the string section was just for one day. But I was in that same studio with more brass than you would ever have in any other format. I'll just never forget it.

This interview has been edited for length and clarity.

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