Since the start of DC Rebirth in 2016, Joshua Williamson has served as the writer on The Flash ongoing series, where he's ushered in a new era of adventures for Barry Allen as he navigated the post-New 52 world. Along the way, the Scarlet Speedster reconnected with old friends and allies as his memories of the pre-Flashpoint reality were restored while contending against new enemies, like Godspeed and Bloodwork.

And now, Williamson's acclaimed tenure on the series is coming to an end, starting with this August's "Finish Line," the beginning of one last, major story arc that will see Barry face off against the Reverse-Flash and his Legion of Zoom in an epic showdown. In an exclusive interview with CBR, Williamson discusses how he began planning for the eventual end of his run, why he turned down an offer to stay on the title even longer and what to expect as his tenure draws to a close along with providing the covers for The Flash #757-762, which will bring "Legion of Zoom to close while launching "Finish Line."

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CBR: So, you're starting "Finish Line," the road to your end on The Flash. When it's all said and done, you'll have been on the title for more than 100 consecutive issues, one of the longest single runs with the character. You've been seeding stuff as far back as at least issue #9. Is this the ending you always had in mind when you first signed on to this book?

Joshua Williamson: Yes, in a lot of ways, and that's part of why it's time to go. When I first pitched this book I had two big stories to tell: I had one story that was the Speed Force storm stuff that became the first eight issues. But then, I had this really big, big idea about what I wanted to say about Barry Allen. I had this huge thing, and I wasn't sure how many issues it was going to take, and I also liked to sort of move and play around with the idea of the DC Universe as a whole. When you're doing a book like this, you have to sort of exist within that universe, and that means being able to work with other people and tie into other events and things happening, so I kind of factored that into it.

But I always knew that this is what I want to say and what I want to do. And when you look at something like The Flash: Rebirth #1, the first issue of the run [from] way back in June 2016, I was already seeding things there. Like, this is the first big story, but this first big story is really just the start of a huge story that I want to tell, and this is the huge tapestry piece of it. So, I always knew that this is what I wanted to end on which is why I was like, "Oh, this is time." Because at one point, after I was done pitching it and working on it, I had the option to continue; DC didn't want me to leave.

We had some conversations about different options I could do, and there was a moment there where I was like "Well, could I keep going?" and we started talking about different ideas and different things I could do with Barry Allen and Barry Allen's story. And then I started looking at it, and they understood when I said "Look, when you look at this story I'm doing with 'Finish Line' and how big it gets, that's the end of the story I've been essentially telling over a hundred issues." It literally would've been issue #101 when you factor in the Rebirth issue, the annuals, [and] things like "The Button" crossover, You factor all of that stuff together, and it's over a hundred issues long, and that's the end. If I keep going, it's going to dilute that or not be as passionate as the stuff I wanted to do. So after looking at all that, I went to DC and said "That's it, it's the end of the story."

Now, that doesn't mean I'm done with the character or the Flash Family. There are still other stories I want to tell with the Flash and, in particular, the Flash Family. There's other characters in that mythology I want to work with. But really, with this story, this is the end, and that's what made me go "This is where I leave." But as you'll see as things go on, this isn't my last Flash story, it's just the end of this particular big story of my main run on the book.

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The last time we spoke about The Flash, you mentioned you were surprised by Barry Allen's The Right Stuff, move-forward spirit. Was there anything about crafting the stories themselves that surprised you?

No [laughs.] I feel like I knew it, there's pieces of this where it was maybe a little different from what I was expecting, but I still got the pieces from it. I got him to here, and this got him to here. It all helps with that big narrative, because when I go back and look at what I was trying to say from the beginning and how that all feeds into everything. When someone reads issue #100 and issue #101, when they go back and see, they'll see that there's all these pieces to get us to this spot. So, Barry emotionally... I don't know, I don't think anything threw me off-guard at all, I always knew the story. And because I knew the big story and what I wanted to say abut Barry in the end and come to these conclusions and the characters around him, no matter what curveball was thrown at me -- because new ideas kind of popped up as I was going -- I always found a way to say "Okay, I'm going to do this story. How does that tie into the mega-story emotionally that I want to do?"

And I was never married to something, like, if it was going to take me in a different direction, I was going to ignore it. Nothing ever got in my way, mostly because it's an emotional story. Like, when "Year of the Villain" was developed, and I had to have the Rogues' story, I found a way to do something with the Rogues and with Barry. In issue #87, when Barry's having that conversation with Captain Cold while they're in the back of the van on the way to Arkham, I was able to get something out of Barry emotionally that leads to what I'm going to be doing in the end. So, it all mattered and all counted. I was able to take it all, and once you get to those last two issues you're going to see that it all added up.

Speaking of "Year of the Villain," any chance we're going to see anymore Super Saiyan/Super Sonic Barry Allen?

Yeah, he does something in one of the issues where he has a couple more moments of that. Not a lot because I don't want to overdo it, but it does happen.

So there was nothing that caught you off-guard?

There were definitely curveballs, but I love puzzles. It sounds silly, but when someone throws that curveball at me, you still got to hit that home run, right? You still got to try. There are definitely things that were thrown at me but you still got to try to take those things and make them work.

You got to put a lot of tools in the toolbox that are already showing up on television, like Godspeed, Bloodwork and Black Hole, which are all kind of showing up right around the same time. What surprised you with how the fanbase reacted to things like that?

In regards to the TV show stuff, I was surprised that Bloodwork with something they picked up and ran with and used as much. I remember when I heard they were using him as a villain, I thought they were using as a monster-of-the-week kind of thing. And then he ended up being the main villain for the first eight episodes of the season; that was really surprising.

When it comes to the readership, something that they gravitated towards that I was a little surprised by the response to Godspeed and how much people really liked Godspeed. I think there's things with "Running Scared" with things between Barry and Eobard that I was really happy with that I see people talk about, that we've added things to their dynamic that weren't 't there before. And all I did was take the pieces that were there already, and I put them together in a big pot when before, they were scattered in all these different stories. People really seemed to respond to that.

I'm glad people really liked "Flash War." That seems to be the one people like the most. Nothing really surprised me, but I'm definitely glad people liked the stuff that they liked. But, with Godspeed, it got the point people were making custom toys and Godspeed cosplay; I didn't really expect that. I just wanted to make a cool-looking villain that had an emotional connection to Barry, so I'm really glad people liked him a bunch.

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"Finish Line" comes after "Legion of Zoom" -- which is like the greatest villain group name, by the way.

What's funny about that is that originally I was going to introduce the Legion of Zoom much, much earlier. It was supposed to be teased in issue #25, but we didn't have enough room. There's actually a picture of a bunch of us mapping stuff out in November of 2016, we had a summit of all these different ideas we had. We had this whiteboard and -- it's really funny because Tom King is the in the picture -- behind him you can see all the plans we had. The Bat-Cat Wedding was on there, all the stuff about Dark Nights: Metal was on there. And on there, you could see the words "Legion of Zoom" next to "25" because I was trying to introduce the idea of them in that story. So even back then, I wanted to use that name and that idea but we didn't get around to it until now. And I'm glad we waited until now, I just wanted to tease it back then.

There's a lot of crazy stuff coming and, what's been great, is I've gotten to work with a lot of artists who have worked on the book before. We have Christian Duce, Scott Kolins and Rafa Sandoval who are all doing the lead-up to the last two issues and Howard Porter is drawing the last two issues. The stuff that we're doing in "Finish Line" is really, really, intense, a lot happens in those two issues. I really wanted to make sure I had no regrets on the book and so there's some really, really big stuff that happens in "Finish Line" that'll make people happy and I wanted to make sure I went out with a bang and was able to tell a really big story with the Flash, the Flash Family and Eobard and say something about Barry by the time we get to that ending. So it's awesome to get to work with these artists -- especially Howard who already has such a history with the character --with these last two issues.

Leaving the book, I wanted to make sure I could finish the story I wanted to tell and -- again -- DC allowed me to do that. Like I said before, they wanted me to continue. But I just looked at it, and this is the end right here. I feel like this is the time to leave; I'll always have more Flash stories to tell, but I feel that this is the place for me to stop and I'm really excited about it. I'm excited to be able to leave the book behind and do stuff because doing a double-ship Flash book for over four years -- because I was working on it long before it came out -- it's been something I did a lot of work on. I put a lot of work into the character and added to the mythology, and I'm just really excited about being able to tell this last, really big story.

You were working on this before your kid was born!

Yeah! I pitched it when my wife was pregnant. I pitched it about five years ago now when I went to C2E2 and Scott Snyder and I were talking and he was like "You should come back to DC!" and I said "I don't know if I want to, this is the only stuff I want to do." H said I should write The Flash and that I should ask and, after that, I started thinking about it a lot. It's funny because I knew I loved the character, and I knew was obsessed with the character. But I've been working on it the past few years, and I've been having these conversations with other people where I realized how much I loved the character and how much I was obsessed with it.

Working on the book has made me much more aware of how much I was in love with the character than I thought I was, because I'm protective of it in some places. I guess that's what surprised me, was how much I loved the character, and I knew it. Like when people mention stories and moments, I'm like "Oh, you're talking about this issue, this panel." Recently, Tom King tweeted a panel from a Flash comic and -- just from that one panel -- I knew exactly what issue it was. I didn't just know the issue, I knew who wrote it, who drew it, what was happening around that panel. It really showed me how much I loved the character, and then I started pitching it five years ago. I've been in this life with Barry Allen for a long time now.

Do you have any regrets?

I don't have any regrets, I guess. It's funny because I had one villain -- I'm not going to say who it is but it may be obvious once people get to the end -- there's one villain I really wanted to use but I could never crack the story. Like, I wanted to use this villain but I don't have a story to use this villain. I just wanted to write them once because I just wanted to touch the majority of the mythology somehow, in some way, I wanted to put my hands on every bit of Flash mythology in some way or another, even if I just hint at it. But I've been able to touch on a lot of stuff and, especially once we get to this last story arc, I think people will see I was able to pull in all this stuff from the mythology. I'm just happy with the way we're ending it so I don't think I have any regrets. I have other stories I want to tell, but I'm not going to tell them in this book...that's kind of a tease for other stuff [laughs.]

Written by Joshua Williamson and illustrated by Rafa Sandoval and Jordi Tarragona, "Finish Line" begins in The Flash #759, on sale August 11 from DC Comics.