After five seasons of Archer, Chris Parnell is already a veteran voice actor, while Spencer Grammer is a relative newcomer to animation. But when the call went out for roles on Rick and Morty, the Adult Swim series created by Dan Harmon and Justin Roiland, neither could say no.

The show, which premiered in December, centers on Rick Sanchez (Roiland), an alcoholic, sociopathic scientist who, after being missing for nearly 20 years, shows up on his daughter’s doorstep looking to move in with her and her family. He soon converts the garage into a laboratory, and be-gins involving his 14-year-old grandson Morty (Roiland) in his insanely dangerous ad-ventures. Parnell lends his voice Jerry Smith, Morty’s insecure, unemployed father who disapproves of the influence Rick has on his son; Grammer plays Summer, Morty’s 17-year-old sister, who’s occasionally jealous of the adventures her little brother has with their grandfather.

With Rick and Morty back at Comic-Con International in San Diego to promote the second season, Parnell and Grammer met with journalists to discuss what fans should expect from the new episodes, working with Harmon and Roiland, and more.

So on Rick and Morty, do you guys record the lines separately or all in one room?

Spencer Grammer: Well, Justin is in there. Is he there when you do it?

Chris Parnell: Yes. He's around.

Grammer: He's there for me too, and he basically directs us for whatever they -- everyone has ideas about what happens, and Dan will have particular notes about certain things that he wants out of a particular scene, so we'll articulate those. It's great. You don't have to necessary follow the linear story line in a way. You get to just get to go and try different ways with that one line, and that can be really, really fun. You can be crying. You can be laughing, and it's great. And it's really quick and fast when they animate them. They pick the best ones later.

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Are you guys busy at work with Season 2 right now?

Grammer: We're in the middle of it.

Parnell: I don't think we're in the middle of it. I think we're doing a lot of this season. I think we're doing more than –

Grammer: More than 10, really. I've done seven, six or seven episodes so far, maybe five or six. So they come every two weeks. They have the storylines written up for a long time and then they'll finish a script in two weeks and they'll get it and they'll record it.

With Season 2 jut around the corner, is there any universes you're looking forward to seeing? Last year there was Cronenberg World, and that was pretty great.

Grammer: I know the season opener has a lot of multiverses, like many, many different universes happening at the same time, so you'll get to see different version of our characters in different realities. It's very ambitious.

Parnell: Especially for the animators.

Grammer: But the animators love it.

Parnell: They love it, but they've got their work cut out for them.

Grammer: I think we were at the Rick and Morty premiere party, and I heard two animators in the bathroom. I was eavesdropping, obviously, in the ladies room. They were saying how much fun Rick and Morty was to animate, like, it's their favorite show to animate. I don't think they knew I was the chick who was voicing Summer. I was just this chick staring awkwardly in the bathroom. But they were like, "I wish I could do more Rick and Morty animation because it's so fun, it's so creative. You have all these different universes and different kinds of characters that they get to create that allows for I think a lot of creativity on all fronts, I think even from our side too. It was fun. And it's just fantastic. They're geniuses." What can I say? It takes a genius to makes a hit show.

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What's your favorite episode from Season 1 that you've done?

Grammer: My favorite one was the one where I was working for the devil, "Needful Things." That was my favorite one, because I like the ending where we go and we beat him up. It was so much fun. I laugh so hard when they got to do that.

Parnell: I liked the one where they're in a simulation and Jerry thinks he's been awarded this advertising trophy.

Grammer: I don't think I was in that one, which is why I didn't love it.

Parnell: I think that's why I liked it.

Grammer: That's why you liked it! I wasn't in the simulation. I didn't happen to be in there. But yeah, your storyline was pretty great in that one. You really made it as a person and a character in a simulated world. It was awesome.

Parnell: So sad. So sad.

Between the character Cyril on Archer and Jerry in Rick and Morty, who would you think would win if they got into a fight with each other?

Parnell: Oh, Cyril would definitely win.

Because of his spy training?

Parnell: Because he's bigger and better built and all of that, but it would be pathetic. It would be sad. It would be a slap fight.

Rick and Morty returns in 2015 on Adult Swim.