On one hand, Ed Helms was stepping into a role with a long tradition of being played by multiple actors, even if Rusty Griswold isn't exactly Hamlet. On the other, he was well aware that by assuming the mantle and taking a new generation of Griswolds on a road trip, he would have to live up to the very large comedic legacy of the "Vacation" films.

Helms joined journalists for a roundtable discussion about taking over as paterfamilias of the clan with a penchant for recreational misfortune, explaining his willingness to risk rebooting a classic franchise, finding the right give and take with on-screen wife Christina Applegate, admitting his Hemsworth envy and breaking down Seal's "Kiss From a Rose."

What was fun for you to make “Vacation” a little bit your own, to keep it true to the spirit of the original, but to own this character and make it distinct?

Ed Helms: I felt like [writer/directors Jonathan] Goldstein and [John Francis] Daley did 90 percent of the heavy lifting in the script. They created a new world and a new family dynamic that felt absolutely in keeping with the Griswold mythology, but also completely fresh and brand new. That’s the only reason I agreed to do the movie – because it felt fresh.

Also, I was in mind for them when they wrote Rusty. They wrote something that felt very organic to me as an actor. Then, really, it was just a matter of shedding that insecurity of “I don’t want to mess this up,” and getting to a place where “This is going to be a blast and cool” and having the confidence to dive in and bring whatever I bring to this world. If it wasn’t such a fresh script and a clean start for this new Griswold family, I don’t think I would have jumped on board.

You appreciated the tone?

Yeah, when I first heard of the movie, I didn’t want to do it. I assumed, like a lot of people, that this was a remake. It’s really, technically a sequel. That just opened it all up for me. Not only did it open it up for me, but it’s funny and surprising to give Rusty his own chance at this. From that point forward, we don’t felt any weight. It was just, “Let’s nail this.”

Part of the magic of this, too, is the magic you have with Christina Applegate, which is key in making the whole film work. Tell me about finding that chemistry with her.

I had never met Christina before this project and was a huge fan of hers. I was thrilled when she was hired, but I didn’t know what to expect. I asked around. I emailed Will Ferrell, and everyone had the greatest things to say. I went in optimistic, and she is just the dream co-worker. She’s so professional.

REVIEW: "Vacation" Will Make You Wish You'd Stayed Home

And as an actor, I’ve seen someone so natural. There is something in the way she delivers her lines that is so effortless. I don’t know how you do that. When I’m acting, I try to make it effortless. I try, but inside I can feel gears turning: "Act this way." She seems to flow and makes it my job so easy and fun, and it’s also a reflection of who she is and her personality, which is just a lot of ease and flow and just enough snark to make her fun to hang out with too. We had the time of our lives, really one of the best movie-making experiences I’ve ever had.

She wanted to have us ask you about the "Combination Pizza Hut and Taco Bell" song.

There were so many stupid jokes in that car. It was a real family trip that way. We were in that car, on a hot set, we couldn’t get in and out very easily. It was just the four of us trying to keep it light, and it became like a real family dynamic. I was concerned that the kids had snacks and drinks. Then, these really dumb sing-along movies that would happen, and that was one of them. [He then sings, “I’m at the Pizza Hut! What? I’m at the Taco Bell! What? I’m at the combination Taco Bell/Pizza Hut!”] It’s a little catchy and has a rhythm that you want to dance to.

Your thoughts on the Chris Hemsworth bedroom scene?

Here’s the thing that nobody knows: Chris Hemsworth has a six pack on his back. It’s mind-numbing. He’s a human praying mantis the way… I’m drifting off into Hemsworth ogling. He’s a beautiful human being.

How was it shooting that scene?

Real hard to keep a straight face. And not just because of the prosthetic, which is super-funny – just as a visual. But Chris’ performance in that scene is comedy genius. Which, to me, is infuriating because I’ve spent my life trying to cultivate my comedy chops, and he’s spent his life cultivating his abs and his dramatic acting chops, which are fabulous. For him to waltz onto a comedy set and be funny as hell, I’m sorry, but that’s annoying! But also awesome, because his performance is why that scene is so funny. It’s not the visual. The visual is the trigger, but he sells it.

Having Chevy Chase and Beverly D'Angelo in the movie is the icing on the cake. How important was it for you as someone who is taking this franchise into a new place that Chevy was there? Describe what it meant to you to have that moment alone with Chevy, actor to actor.

It can’t be overstated how important and wonderful it was to have Chevy and Beverly on set with us. It was the ultimate affirmation that this was OK. There was a little bit of insecurity in all of us making this movie, because it’s such a sacred cow, it was for me, and such a precious world that we don’t want to be the ones to mess it up. And to get a giant vote of confidence from Chevy and Beverly, which is manifest in their eagerness to be in the movie with us, was the ultimate high-five and pat on the back for all of us.

It was awesome on a spiritual level that way, I guess, but also that day, having them there on that day was fun. They really settled into those characters again, and their dynamic, not just as the Griswold, but Chevy and Beverly are hysterical together. And I got to ask everything I wanted to know about comedy in the ‘70s, which was the heyday for me. And Chevy was an open book and fun to talk to about all that stuff.

You get to sing Seal's "Kiss From a Rose" a few times. Did you like that song?

I liked it before we started shooting and now I’m ready to blow my head off if I hear it again.

”Vacation” opens today nationwide.