Greg Grunberg talks reuniting with Alias costar Bradley Cooper in A Star Is Born

One of the pleasant surprises of A Star Is Born — and there are many — is the mini Alias reunion that takes place in Bradley Cooper’s critically acclaimed musical drama.

Cooper, who played Will Tippin on the ABC spy series, cast his Alias costars Greg Grunberg and Ron Rifkin in small but pivotal roles in Born. Grunberg portrays the driver for Jackson Maine (Cooper), and Rifkin is Jackson’s therapist in rehab.

EW recently caught up with Grunberg, who’s currently shooting Star Wars: Episode IX in London under the direction of good pal (and Alias creator) J.J. Abrams, about watching Cooper make his directorial debut and witnessing Lady Gaga transform into an actress.

ENTERTAINMENT WEEKLY: So, did Bradley just call you up and ask you to be part of this?
GREG GRUNBERG: Yeah, we remained friends, close friends over the years, and he is the greatest ever. I love him so much and couldn’t be happier for him. The odd thing is the role that I play in the movie is something that I played in life many, many years ago. When I was 19, I was Joel Silver’s driver for a year, the producer.

So Bradley called me up and he’s like, “Look, there’s a role, and it’s not what you’re used to doing, but….” I’m like, “Bradley, I don’t care if you ask me to do craft services.” I love him so much, and I wanted to support this project. But Bradley goes, “This guy, he, in a way, has a closer relationship to this driver than he does to a lot of people. They have conversations.” One of the things that was really great, and you saw it in the movie, is we’re driving around, and Brad was like, “Hey, what’s going on with Bennyreens? Still playing baseball?” And my son’s name is Ben and we used to call him Bennyreens. And I’m like, “Yeah.” I’m like, “Okay, I guess we’re improv-ing.”

Did you know Ron Rifkin was going to be in it too?
No. I remember exactly when Bradley told me, and he goes, “By the way, Ronnie’s in the movie.” And I said, “What?” He goes, “Yeah, I called him up and said, ‘This role is… you would kill it.’”

J.J. does the same thing. J.J. calls me up and says, “Hey, would you do me a favor and be in Star Wars?” They’re so humble and ridiculous. And so it was the same thing. Ron Rifkin is one of the best actors, I think, ever. And he’s got the same quality that a Henry Winkler has, where you just love him. And he’s so genuine, so sweet, so real.

How was Bradley as a director?
He was so at ease, and really in his zone. He was so comfortable doing it, but at the same time open and collaborative and great. I hate saying this, because I don’t want to put this moniker on him and he just started, but great directors do that. They get to the set and they can make decisions on the fly. They can work with what they have. He’s like an on-the-day director. It’s always like, “All right, we’ll figure it out on the day.” And he does his homework. He was so prepared. It just was so great. He’s so in his element, and he will definitely be doing this for the rest of his career, for sure.

And what was it like to see Lady Gaga take on her biggest acting role?
She’s such a genuine person. A couple times between takes, she actually said to me, “What do you think? Was that all right?” And I’m like, “What?” I’m such a fan of hers. She’s so real. She’s so good. I was thrilled. I was thrilled to be working with her. And then I saw her at the wrap party and she runs up and gives me a hug. She’s so great.

In the parking lot [where Gaga first sings “Shallow”], I’m standing there with the Cheetos and I had the hardest time not turning because she’s belting this out. She has the most pure, beautiful voice ever. And that’s where you go, “Oh my God.”

When Bradley first showed you the film, what was your reaction?
There’re so many things that I’m proud of him about, and he just blew me away. I didn’t know how to articulate how emotional it made me. I said, “Bradley, that’s one of the most beautiful movies I’ve seen.” And J.J. had the same reaction.

Now, the other amazing thing, selfishly, is I have this old red pickup truck and he used it in the movie. That’s my truck in the movie. He saw it one day. I pulled up to my trailer. And he was like, “Whose truck is this? I want to use it.” I have such a personal connection to this movie in so many ways.

Greg, you’re also a musician [in the group Band From TV]. What did you think of Bradley’s musical talents?
I was so impressed by the fact that he did this, and not only did he do it, he did it naked as a musician because he recorded that live. It wasn’t like he did it to a track.

I’ve had so many great people onstage with us in the band for charity. I’ve never asked him because I didn’t know he does that. He’s kept that a secret from so many people for so long, and he was really, really great. Of course, the first time we start talking about the movie, I was like, “Look, I’ll play the driver, but who’s your drummer?”

You’re currently shooting Star Wars: Episode IX. Can you tell me anything?
I wish I could. You know, what’s so crazy is that I don’t even know anything. I’ve been here for three weeks and I’m like, “Oh, my God.” Every day. And J.J. looks at me with this wry look on his face like, “I told you it was gonna be great.”

Does this mean we’re any closer to an Alias reunion?
I wish. I really wish. We just had our 20-year reunion for Felicity at the ATX Festival. I hear it all the time at the comic cons I go to and the interviews I do. Everybody talks about it. I think it would be great if there was a movie.