GREG GRUNBERG is utterly in his element at San Diego’s Comic-Con, perhaps because he embodies so many facets of America’s big daddy of pop-culture festivals.

Grunberg is best known as an actor, from such shows as “Heroes,” “Alias” and “Felicity” to his current double duty in Hollywood’s big-two space franchises, “Star Trek” and “Star Wars.” His producer credits include “Movie Nights” and “One Question Interviews.” And he is co-host (with Kevin Smith) and executive producer of the talk show “Geeking Out,” which debuts tonight at 10 on AMC with a special Comic-Con episode.

Now, he’s a comics creator, too.

Grunberg has teamed with his friend-in-geekdom, “Imagine This” cartoonist Lucas Turnbloom, on “Dream Jumper” (Scholastic Graphix), a graphic-novel series that debuted this summer with “Book One: Nightmare Escape.”

“Dream Jumper” not only fulfills a creative dream of Grunberg’s, it also emerged as something of a brainchild from Grunberg’s own child — after his son had a dream — so the comic feels imbued with the magic of childhood and the paternal love of parenthood.

As Grunberg and Turnbloom prepped for Comic-Con, The Post’s Comic Riffs caught up with the co-authors to talk graphic novels and geeking out. (This interview has been edited for length and clarity.) 

MICHAEL CAVNA: It seems only fitting, guys, to ask about your own origin story. How did you two come to decide to collaborate on this: Were you fans of each other’s work before this?

LUCAS TURNBLOOM: I’ve been a fan of Greg’s work for years, which is how I learned about his website for epilepsy awareness called Through the epilepsy charity, I had started doing a webcomic called “4G” (Four Geeks). The idea was to use the comic to help bring new readers to the site every day. Entertain and educate. I worked on “4G” for more than a year.

GREG GRUNBERG: Yeah, and by the way, anybody who is willing to do the amount of work that Lucas did for the epilepsy community and for me without ever meeting me or wanting anything in return has got to be a great person. So I knew that Lucas’s heart was in the right place, and clearly he is the most talented illustrator/storyteller that I know.

LT: Greg’s an incredible storyteller, as well. And the idea for “Dream Jumper”? Blew me away. Still does. But I’m getting ahead of myself. Skip ahead about a year or so after I created “4G,” to San Diego Comic Con. Greg wanted to meet there and sign some posters to help promote the strip [and the site]. But instead of focusing on “4G,” Greg told me about a dream his son had, which was the seed for “Dream Jumper.” He asked what I thought could be done with it, and I told him this needs to be a graphic-novel series now — which is the same thing his friend J.J. Abrams told him. We were both incredibly excited. I went home that night and started working on a really rough draft. Greg and I would spend the next several months creating and writing what would become “Dream Jumper 1: Nightmare Escape.”

GG: Yes, my son had this dream. Yes, I came up with the seed of an idea for what I thought would be incredibly interesting and powerful and visceral in an immersive world that had not yet been explored — at least for kids. J.J. told me that he thought this was a graphic-novel series and that I could definitely develop into much more than that, but that it should be a graphic novel first. Having absolutely no knowledge of that world, I mentioned it to Lucas and he immediately responded to it and got so excited about it. And the fact that we are now here partnered with my our dream company in the publishing world, Scholastic/Graphix, is a dream come true, pun intended.

MC: Trying to co-write a creative project has strengths and challenges. Could you describe how your own co-writing process worked? Was it more talking it out together, or each revising the other one’s ideas on paper or screen?

LT: All of the above. When we started the story, Greg and I would spend a lot of time emailing, talking on the phone, texting, carrier pigeons, etc. When it was time for writing the dialogue, and making sure the story makes sense, we’d meet in person and talk the story out — which is always a blast, by the way. Greg and I have a similar sense of humor, which makes it really easy. It also means the first draft usually has a lot of cussing. The most challenging part is the distance between us. I live in San Diego, Greg lives in L.A. If I could convince Greg to let me move into his shed, things would move a lot quicker.

GG: I keep a lot of scary things in that shed so I really don’t think Lucas means what he saying. Plus, I was charging way too much rent. But Lucas is absolutely right — it’s been a collaboration since the beginning, and the distance has made it a little difficult. But through technology, we have been able to FaceTime, text, email and just get it done. But it has been one incredibly fun conversation after the next, and we have laughed so much and surprised each other a great deal. It’s been the most fulfilling collaboration that I’ve ever experienced. Maybe I should take all of the people that I work with and move them out of town. Maybe that’s the key. They say absence makes the heart grow fonder — maybe it makes the brain more creative, as well. I think that’s it: If Lucas and I share an apartment together, we’ll be at each other’s throats.

MC: “Dream Jumper” has a profound theme of parenthood — and of our love and deep concerns as parents — running through it. Greg, could you speak about the germ of this story — the inspiration — as it relates to you and your own son?

GG: Well, this is an example of a parent’s taking advantage of a child’s dream. My son, Ben, will not admit to it, and he’s probably right, but I remember his dream having a little more detail than he does. He was a lot younger and he woke up and had a vivid dream. And the idea of it being so vivid, it got me thinking that maybe our dreams take us into another world. And wouldn’t it be amazing if the conduit to that other world was a boy and his ability to jump in and out of his friends dreams? And save them like a superhero through their worst fears and nightmares? I could not stop thinking about it. I couldn’t stop dreaming about it. And when I mentioned it to Lucas, the light went on in such a bright way. And I know both of us have been dreaming about it ever since. But with the fun — and wish fulfillment that certain dreams have — comes the flip side, which are the nightmares. We all experience them, and we are all so relieved when we wake up and realize that they’re not real. But what if they were? That’s the essence of “Dream Jumper.” What if they were?

MC: Ben — your lead character — pops off the page from the very beginning; he feels fully formed and realized. Could you talk about what Ben means to you as a character?

GG: Ben is a really smart kid. He’s a lot of fun. Yet he feels like an outsider amongst all of his other friends. I think he knows he’s special, but he doesn’t quite know why. And in that discovery, we are along for the ride with him. The TV show “Heroes” had a lot of the same themes — where ordinary people wake up and each one of them is experiencing a change in their life and a moment that defines them, but in mysterious and crazy ways. And the fun ride of it all is to discover these powers that they all had, and at the same time, they were discovering and exploring just how powerful they were. There’s a lot of mystery that goes with that, a lot of excitement and a lot of “be careful what you wish for” moments.

Ben has a pretty messed-up family, yet his mom cares about him very much. The pieces of his family and the unknown about the history of his family, and exactly why he has the ability to jump in and out of his friends’ dreams, is revealed a little bit in Book One, and a lot more in Book Two, and then in a really powerful way in Book Three. But the twists and turns and surprises and cliffhangers only get bigger and bigger as our book series goes on on.

MC: Fellow comics creators have told me they know they’ve got “it” when their characters practically “speak” to them — it becomes organic, as if the [illustrated] actors are so alive they’re seemingly providing their own dialogue. Do any of your characters “speak” to you yet?

LT: Oh, for sure. Ben’s voice is so clear in my head, he really writes himself, [as does] Ben’s sidekick, Jake, [whose] sarcasm is absolutely my own. And of course Lewis, the kindly rabbit. Like Lewis, I try to bestow wisdom upon my kids, but rather poorly. Heck, I am still just a big kid. But I must confess, I rarely understand today’s youth-speak. “Sick? Who’s ‘sick’?” Things are very confusing in my home, sometimes.

GG: That’s exactly it. Lucas and I are two old farts just trying to recapture our childhoods, and we are stealing from our kids at every level. I absolutely love the fact that even at my age today, I don’t consider myself anything but a kid. I’m a goofball. Immature. And I don’t ever want to lose that unconditional exploration and humor and fun that come along with being a sponge and soaking up everything around you.

I think hopefully our characters are defined from the get-go, because they certainly are in our minds. The character of Jake is such a fun character and kind of embodies who I was as a kid. My friends were much more powerful and creative than I was, but I was right there to take advantage of that creativity and explore how we can best use it to my advantage. And the character of Ben? Can you even imagine if [suddenly] you realized that you could dive in and out of your friends’ dreams, and yet were suddenly given the title of the chosen one? That’s good and bad. Fun and not. Scary and exciting. That’s “Dream Jumper.”

MC: Greg, your lifelong friend J.J. [Abrams] wrote an impassioned foreword for “Dream Jumper.” Are there any aspects of Book One that reflect moments or memories from your own geeking-out childhood with J.J.? 

GG: Growing up, J.J. was this incredibly talented little kid, and I was his chubby friend who was completely enamored and fascinated with every one of the incredible things that he was able to do. I was along for the ride. I was the Jake to his Ben. And I think that resonates in the book. But I think we all have friends like that that we aspire to be, and people that we absolutely gravitate toward and want to be around as much as possible. J.J. has been such a creative inspiration in my life at every step. Not just the fact that he’s brilliant and he’s given me so many great opportunities in my career, but also that he motivates me and he’s an example to me that instead of talking about things, I should actually be doing them and trying to create them. And once in a while, you get incredibly lucky and you partner with someone like Lucas who can help you make your dreams a reality.

But it’s all about the work. And if you love your work, then you can’t wait to jump into it at every waking moment. Or not waking moment, as it were.

MC: Part of what I like about Ben’s look is that it’s relatively timeless within modern American culture — with the red hoodie and sneaks, it could be the ’50s or ’70s or today. Could you talk about the character design of Ben?

LT: I’m a child of the ’80s. So when it came time to design Ben, I went right to my childhood wardrobe: hoodies, jeans and Chuck Taylor [Converse] shoes. In addition to “Dream Jumper,” you’ll notice that in a lot of my work — including my children’s book “Dragon & Captain” — characters often wear “Chuck Taylor” shoes. They’re just a lot of fun to draw. Also note: If Ben ever graduates to flannels, Metallica shirts and deadpan expressions, that’s High School Lucas’s wardrobe.

GG: And also if you look at the environment that we’ve created, then you’ll see a lot of the two of us when we were growing up. You’ll notice Ben has a [number] of interests that he kind of dabbles in a lot, but he’s a master of none of them. So when he finds his ability and power … he’s finally coming into his own and realizing his purpose and his place in this new world. That’s empowering for anyone, but especially a kid who feels lost in the real world.

MC: A wise rabbit named Lewis who can seemingly jump time? I detect a warm nod to “Alice in Wonderland.” Are there any authorial influences or notes of homage we should know about?

LT: Obviously, Lewis’s first appearance is a definite nod to “Alice in Wonderland.” But “Dream Jumper” is very much its own thing and not a sequel to any of Carroll’s work. The Harry Potter, Oz and Narnia books were also very influential in the writing process. As well as movies like “Star Wars” and “The Matrix.” Greg and I have an unhealthy obsession with pop culture.

GG: Who doesn’t geek out about this stuff? I think that’s why this resonates with so many people, because there are elements and influences from so many of our favorite TV shows and movies and books. They say there are no original ideas, but some of the best ideas are what mold our dreams and what … certainly helped us to create this world on these characters. But unless the characters you create are relatable and you want to take [a] journey with them, none of that matters. So it always comes down to whether you care about the characters, and for me and Lucas, I think it comes down to family, and that’s really at the heart of every great story and certainly at the heart of our story.

MC: I was fully pulled in by the embedded messages and plot points concerning overcoming our fears and discovering our own strengths. What are some of the themes of your Book One that you hope young readers especially will take from your debut story?

LT: I think everybody at some point in their life doubts themselves. God knows I do. “Can I finish this dessert?” It’s a perfectly normal feeing. One thing I really want kids to take away from this is [that] when the odds are against you, never, ever give up. Even if something seems impossible, never stop trying. And by the way, I finished that dessert. It was delicious.

GG: Lucas also finished my dessert, which, by the way, is not fair at all. So … at San Diego Comic-Con, I’m buying a dozen donuts and I’m gonna make Lucas watch me eat them all.

LT: He’ll really do it. But it’s the only way I’ll learn.

GG: I hope kids, and anyone who reads our “Dream Jumper” books, will see that we are all special and we all have a unique ability that defines us, and we need to embrace it and not be afraid of it. They’re going to be massive challenges, but that only makes the celebrations bigger when you overcome them.

MC: As parents, did you bounce this story off of all your kids, either during creation or after publication, for feedback? And congratulations on selling the film rights. As protective parents of “Ben” and the gang, will you insist on some creative control on screen — or are you turning over that control to new cinematic “parents”?

LT: I definitely sought my kids’ advice when designing the characters. Especially with Lewis and the Nightmare Lord. “Hey, kids. Does this guy scare the c___ out of you? It does?! Great!”

GG: I guess I’m a better parent than Lucas is, because I would never intentionally scare my kids just so that I could see what works or not. My boys are delicate flowers that need to — blah blah blah blah — of course we did! Our kids are our test subjects. Our crash-test dummies. My kids are scarred for life, but who cares? That just makes for incredible characters in our book.

I’m kidding, of course. But, yes, if we didn’t have kids, this would be a lot more difficult to relate to, and some of the best ideas that we have for story and for characters have come from our kids and our kids’ friends and the relationships that they have. Got to keep it real.

LT: After we got the proofs back for “Dream Jumper,” I gave copies to at least 10 different kids and watched them read it cover to cover. Without giving away any spoilers, when each kid got to the big reveal on page 176, their jaws dropped, their eyes looked up from the page, they smiled and said, “No way!” Every single kid. How awesome is that?

GG: And then their parents said, “Get out of my child’s bedroom — they’re trying to go to sleep.”

LT: In terms of the film, I think we are in the best of hands with Paramount. J.J. and Bad Robot are some of the greatest storytellers of our generation. Of course, we would be happy to give any suggestions if asked, but we trust them completely on this. Okay, let’s be honest — I’d be happy just sitting at the snack bar at Bad Robot.

GG: Yeah, we are so lucky to be partnered with Paramount and Bad Robot. And [I] cannot wait to see how they take this world that we’ve created and bring it to the big screen.

MC: Lastly, is there anything you’d like readers to know about your new show [tonight], Greg?

GG: I just want to thank everyone for embracing all the stuff that Lucas and me and Kevin Smith geek out about. And hopefully you’ll enjoy watching me and Kevin — two big, white guys — sit in recliners and get geeky. Our show, “Geeking Out,” premieres on AMC with a big San Diego Comic-Con special, and then we have eight episodes that start airing in August. It’s gonna be a blast and we’re gonna be covering, and be giddy about, things like “Dream Jumper” and “Star Wars” and “Star Trek” and “The Walking Dead,” etc.

Dream big!

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