WARNING: The following article contains spoilers for The Flash #753, by Joshua Williamson, Howard Porter, Brandon Peterson, Hi-Fi and Steve Wands, on sale now from DC Comics.

As Barry Allen's most hated foe, the Reverse-Flash has played a prominent role across writer Joshua Williamson's acclaimed run on The Flash, the villain has raced beyond life and death to make life hell for the Scarlet Speedster on multiple occasions. The ongoing story arc of Williamson's long run, "The Flash Age," has Barry and Eobard Thawne do the unthinkable and team-up to stop the new, time-traveling villain Paradox as he threatens to upend Barry's entire history within the DC Universe's space-time continuum.

In an exclusive interview with CBR with preview pages from The Flash #754, Williamson shared how he decided to unite the two longstanding enemies against a common threat in Paradox, the epic stakes of the story and a tease of what's coming next.

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CBR: With this story, you've got Barry Allen and Reverse-Flash teaming up to take on Paradox through time, this cosmic villain that evokes the Anti-Monitor. What made you want to team up Barry with Eobard Thawne to take on a threat like that?

Joshua Williamson: When I was building up a lot of the stories I was going to tell about Reverse-Flash -- the major events that I wanted to tell with that character -- I wanted to build a villain that they had to team up against. I know that's very simple, but I liked the idea of Barry and Eobard having to team up against a villain. That's something we haven't really seen before, not at that level; because they hate each other so much, especially Barry. It's something he'd never consider doing. And way back when, when we were planning "Perfect Storm" and talking about "Flash War," when you go back to [issues numbered in] the 20s, like around the time of "Running Scared" and issue #25 when we're coming out of "The Button," was when I was figuring out what "Flash War" was going to be and what I wanted out of it.

And I started building this giant tapestry of what I wanted to do with my time on The Flash and the stories I wanted to do. And I had already been seeding things as far back as the Rebirth issue [that launched the series in 2016]; issue #9 was a big issue. So I started mapping all this stuff out and was figuring it out and decided to come back around to this stuff. And so much of my story is about Barry and Eobard, that conflict between the two of them and the relationship between the two of them. I wanted to put them on this rollercoaster ride over the years and have them get back to a place where they're in scenes we've never seen them before, like them running together side-by-side and then going up against somebody. That was all-important and big part of this tapestry that we were building.

Looking at Paradox and talking about what I wanted to do with him, I wanted to use him as a driver for that relationship between them and that conflict and what he represented for Barry and the mistakes that Barry had made. And time-travel shenanigans is part of Barry Allen's story, and it also ties in with Eobard. That's why when you go back and look at things like issue #9, Barry has a vision of the future and there's little clues like a ghost of Eobard in that issue. And you look at The Flash Annual #1, Commander Cold and Renegades are talking about Eobard and they say the one good thing he ever did was put that one person in Iron Heights -- that was Paradox. It was always just building the seed for this really big story which is "The Flash Age" -- which is Barry and Eobard -- and then "Legion of Zoom," which leads into an even bigger story. It's always about building, it's always about putting pieces on the table so that I can tell even bigger stories. So, that's really where that came from: I'm going to have Barry and Eobard team up against a villain, that's the get for this story.

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The Reverse-Flash has played a huge part across your entire run, not just Eobard in stuff like "The Button" but also Hunter Zolomon in "Flash War." While you've certainly made a strong case for Captain Cold and Gorilla Grodd, is the Reverse-Flash the definitive Flash villain?

Yeah, of course! I think some of those other villains are going to come in and out for really big stories. Like I told a Gorilla Grodd story with "Perfect Storm," and I've done a bunch of different things with Captain Cold. But at the end of the day, I think it comes down to Reverse-Flash being on a much more personal level, and not just because of him killing [Barry's] mom. Even before he killed his mom, I was re-reading the issue where Barry and Iris got married and the Reverse-Flash is in that issue. And then you look at something like "The Return of Barry Allen," which I think is the best Flash story of all time, the Reverse-Flash is obviously a major part of that story. And you look at the Geoff Johns The Flash: Rebirth, and that character is so important on a personal level to Barry and has been a part of these big moments.

I think on an emotional level, they're much more connected than some of the other ones. There's a respect between Flash and Captain Cold, I think Captain Cold represents this kind of blue-collar aspect of Barry's personality. He's a criminal, whereas Grodd is this monster who wants to rip Barry apart and steal the Speed Force from him. And what the Reverse-Flash wants, really, is to be Barry. He wants to be a hero, and he wants to be Barry's friend. Like when Thawne looks at Wally, he's jealous. When looks at Impulse and Kid-Flash and even Iris, when he looks at these people in Barry Allen's life, he gets frustrated. Like, "He picked all of you, why did he pick the Flash family? And if the Flash family is so big, why can't I be part of it?" And there's a lot of anger and frustration there and that's why it's so much more personal and that's why I think he's his greatest enemy and I explore some of that stuff in there about him being his greatest enemy.

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With that said, does that make "The Flash Age" the best day of Eobard Thawne's entire life?

Oh, yeah! He's always wanted that, and we play with some of that stuff later when we start to get into "The Flash Age" and "Legion of Zoom." Eobard's an interesting character because he's from the future, he's the curator of the Flash Museum, he went to the Time Institute, he studied time and he he was obsessed with the Flash. There are bits and pieces of time that were lost because of the Great Disaster, and we've explored that a little bit and we'll explore that more later. But when you go back and look at all the stuff with Thawne, one of the big things that Eobard had going back to "The Return of Barry Allen" is he had Iris' book. Eventually, Iris writes a book on the Flash at some point that's a real history of Barry Allen and all the speedsters. She writes this book and Eobard gets his hands on that and part of the frustration is that when he reads that book, there are chapters about him in that book.

When you think about it like that, Eobard is super-far into the future, he knew his own history. He knew how he was going to die, he knew Barry was going to snap his neck, and that messed him up. But even now, a couple times in this story, he mentions to Barry during "The Flash Age" that he sort of knows how this stuff is going to play out. There's only one part, in issue #755 and at the end of the last issue too, where he says "Oh, this is different!" but we don't know if he's lying. There's parts where he says "I know this was going to happen and play out this way," but things are playing out differently than he thought because of Paradox, but he's still playing a bigger game that we'll eventually get to. We'll eventually see that it's this giant game that Eobard's been playing all along.

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Speaking of time-travel and the Legion of Zoom, the solicits revealed that you're bringing back the Tornado Twins.

Yeah, we teased them back in The Flash #26, and this continues some of the stuff from that but they have a couple of cool scenes coming up. They're very angry.

For the uninitiated, they're related to the Flash.

They're his children! There's some timey-wimey stuff going on there that'll eventually be explained but, yeah, they're his children from the future that he never really knew. When Barry went back in time to be involved in Crisis on Infinite Earths, he left Iris in the future and did not know she was pregnant when he left. And so she had these children who become XS' mom and Bart's dad.

Speaking of Bart, I know Impulse is busy with Young Justice these days but are we going to see Bart come back?

Yeah, he's on a cover coming up soon, so he'll be back. I was actually just talking to [Young Justice writer Brian Michael Bendis] about it last night so, yeah, he's coming back soon.

With the Tornado Twins coming back angry -- and Hunter Zolomon had spent time in the future as did Eobard -- does Bart represent a more hopeful future?

Yeah, and there's a couple aspects playing into that idea in the storyline after "The Flash Age" stuff right now, and setting stuff up with Paradox and how Paradox represents [the question] "Why should I have hope in Barry?" is a big part of the Paradox stuff and that'll lead into why Bart comes back.

To beat Paradox, a villain representing time-travel and the consequences from it, Barry and Eobard have to travel through time. Will they have to pay the piper because of that?

Uh, maybe! We'll see that because of Paradox's powers, he absorbs the energy released when a paradox happens. Whenever a change in time happens, he absorbs that energy. So that energy doesn't go anywhere, it doesn't rewrite time, but that can't be stable. It can't be safe. And that's something that we see in issue #755, we'll see that there has to be some kind of cost; it can't be stable to keep changing time in that way. There's definitely going to be some heartbreaks coming. There'll be cool stuff and cheering, but there'll also be some heartbreak.

Written by Joshua Williamson and illustrated by Rafa Sandoval and Jordi Tarragona, The Flash #754 goes on sale on May 26 from DC Comics.