Marc Guggenheim has built stellar careers in both television and comic books, and despite keeping busy as the co-showrunner of The CW's "Arrow," he just can't stop creating and working on even more new things.

Unless you've been living under a rock, you probably know that The CW is about to debut its third DC Comics-based series this week, "DC's Legends of Tomorrow," co-created by Guggenheim, Greg Berlanti & Andrew Kreisberg. "Legends" follows a rag-tag group of heroes and villains established on "Arrow" and "The Flash" who are assembled by time traveler Rip Hunter (Arthur Darvill) for a new mission -- traveling through time to stop Vandal Savage (Casper Crump) from wrecking the future.

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Speaking to Jonah Weiland in the CBR Speakeasy, Guggenheim discussed what sets "Legends of Tomorrow" apart from everything else on television, why the show stars the characters it does and how each episode is different from every other. He also discusses "Arrow's" mystical turn in Season Four, how that allowed for John Constantine (Matt Ryan) to pay a visit even after his own series on NBC was cancelled, and whether we can expect a return engagement. Guggenheim also talks about why he never wants to stop writing comics and the draw of his new "Agents of SHIELD" ongoing series from Marvel, which allows him to scratch some of the same itches in the Marvel Comics Universe that "Legends of Tomorrow" allows him to do on television.

In the first part of his interview with CBR TV, "Arrow" Guggenheim explains the genesis of The CW's third DC Comics-based series and what sets it apart from everything else on TV -- including "Arrow" and "The Flash." He also discusses the slippery slope that is time travel, whether or not the series is inherently more difficult to create and produce, and which character relationship has surprised him the most.

On why "Legends of Tomorrow" centers on lesser known DC heroes:

Marc Guggenheim: We had great actors. We had Wentworth Miller. We had Dominic Purcell. We had Caity Lotz. We had Brandon Routh. We had Victor Garber. We just, we had them. Already. I think a good chunk of television, it's really about casting. We had this incredible cast so it would kind of be criminal, from a TV perspective, not to build a show around these amazing actors.

It was very much a function of, we were thinking about, "Are we gonna do a third show? We're only gonna do it if it's different enough. It's gotta be its own unique thing." And sort of we were having our own conversations and Mark Pedowitz was doing his own thinking, he's the head of the CW, and we arrived at the same math, which is, "Hey, wait a second. We have these incredible actors playing these great characters -- there's a show there." And that's really where it started.

On whether a show like "Legends of Tomorrow" is harder to create, produce and market than "Arrow" or "The Flash":

It is. We definitely doubled down on the degree of difficulty. It takes, you know, the visual effects established on "The Flash" and applies them to all these different characters, all of whom have super powers or abilities -- we went crazy. There's a part of me that wants to say, you don't ground it, you just let it go nuts. And there's a certain element of us certainly doing that. I think the way you ground it is it's in the characters. I always say, people are gonna come for the spectacle, but they'll stay for the character dynamics. The spectacle, the visual effects, the production value, all that's well and good and it'll hopefully get people to watch, but eventually that becomes old hat and eventually you have to deliver the goods from a storytelling perspective and you can't just throw visual effects at everything. I think that's what we've done.

The first two episodes were originally conceived of as one, two-hour event, and we ended up breaking them up into two episodes. That's probably sort of why you feel like, "Oh, Episode 1 is this, Episode 2 is that." I will say, we're now writing Episode 12 and there is not a single episode I can point to that's like any other. This show is very unique in the sense that it literally is a different thing week to week to week to week. There's no villain of the week to sort of ground us from a storytelling perspective -- it really is its own animal. If you don't like -- I'm picking numbers out of the air -- if you don't like Episode 4, stick around, Episode 5 is totally different.

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On the perils and promise of time travel:

I'm always the first to admit we are incredibly fast and loose with time travel rules. I always like to say, if you're someone who is turning in purely for the strict rules of time travel, and how they will be articulated and followed to the letter, honestly, probably not the show for you. The show uses time travel and we go to different corners of the DC Universe -- the show functions on a lot of different levels. One of the reasons I'm proud of it is that it works as a character drama -- it's almost like a family drama -- it works as spectacle, it works as a comic book come to life. It also, quite frankly, it works as this total crazy, nutbar combination of things. And that combination of things is really a love letter to the DC Universe. When you say which corners are we visiting, we're visiting them all. We're in prep on an episode right now that takes place in the Old West, we meet Jonah Hex. The show's a love letter to the DC Universe.


In the second half of the interview, Marc Guggenheim explains when in Season Three the show's writers knew what direction Season Four would take, how that allowed for "Constantine's" Matt Ryan to visit, and definitively explains fans can expect to encounter him again. The busy writer also talks about how he maintains his hectic schedule and why, amid many other projects in both TV and comics, he decided to tackle Marvel's new "Agents of S.H.I.E.L.D." ongoing comic series and the goals he has set for himself in the Marvel Universe.

On why this season of "Arrow" introduced occult and supernatural elements:

Each season has sort of required of us to come up with a theme or come up with a central concept behind it. In Season Two we sort introduced the idea of metahumans, in Season Three it was the League of Assassins. We were looking for something for Season Four and I think, you know, we always get to a point in the previous season where we start talking about the next season. We got to a point in Season Three and we were talking about the lazarus pit and we were talking about R'as al Ghul and there's this idea of mysticism that we really haven't a) explored on the show apart from the lazarus pit but b) fits very much into the voice of the show, and the take and tone of the show. If you go back and look at like, I think it's episode 3x15, Oliver basically says, "I've seen some stuff you can't explain." That was us sort of -- we love to plant a flag and say, "Look for that next season." And that's when we knew what we were gonna do in Season Four.

On whether John Constantine could have ever visited "Arrow" if "Constantine" remained on NBC:

I'm gonna get in trouble for saying this, but, dammit, who cares. Back when "Constantine" was on, we were talking about a crossover and then "Constantine" wasn't on so we stopped talking about a crossover. And then it was like, was it gonna show up somewhere else. Well, we can't talk about a crossover now. It took a while, but yeah, it was something -- I think it was actually something Matt Ryan and Stephen [Amell] started talking. It was always in the cards.

On whether another Constantine visit could happen:

When we were given the character, we were given the character with the understanding and the agreement that this was a one-off.

On what drew him to write the ongoing "Agents of S.H.I.E.L.D." comic book:

To answer that question, I have to answer the question why comics in the first place. Because you're right, I'm busy with television, why write comics, it doesn't pay as well. I do it really for the love of the game. I love writing comics, and I love bouncing back and forth between the Marvels and DCs, where it's the characters I grew up with, and the creator-owned stuff like "Stringers" and "Jonas Quantum" that I'm creating on my own. And I love working with the folks at Marvel -- I probably should say that because of DC -- but I love the books at Marvel and I've been working with them for over ten years now and they're amazing.

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The way "Agents of S.H.I.E.L.D." quite frankly came about was, it was like last June, I went to lunch with a whole bunch of the Marvel editors I've been working with, because a) I was in town, and also I was wrapping up my "Secret Wars" tie-ins and everything. And I was like, "Oh, I'm kind of running out of stuff to write." And pretty much at the end of the lunch [editor] Katie Kubert said to me, "Really? Are you really available?" "Yeah, I'm totally available." She's like, "I could really use a pitch on 'Agents of S.H.I.E.L.D.'" There was a split second where I thought, that could really be weird if this ends up happening. For the longest time I think people put "Arrow" and "Agents of S.H.I.E.L.D." in competition with each other, but at the same time, again, because I do it for the love of the game and I love the Marvel Universe, I really got excited about the idea of doing "Agents of S.H.I.E.L.D." essentially as, like, this could allow me to visit every corner of the Marvel Universe I could think of. Unlike other Marvel books I've done where it's X-Men or Spider-Man or Blade where you're in that corner, what's great about "Agents of S.H.I.E.L.D." is it goes everywhere and they interact with everybody.

My sort of high-concept for the book is it's "Mission: Impossible," it's James Bond, but unlike James Bond and "Mission: Impossible" where they go to these exotic locales and it's all about visiting different places, different countries, this is different corners of the Marvel Universe. I try very hard -- and like Paris appears in the second issue -- but for the most part I want to go to Wakanda, I want to go to Attilan, I want to go to Genosha, I want to go to these different places that are unique to the Marvel Universe. That's just so much fun for me, and it's worth, quite frankly, it's worth making time for. It's been a blast to write.

Stay tuned to CBR News for more on Marc Guggenheim's many projects.