The Flash type TV Show network The CW genre Superhero Where to watch Close Streaming Options

The Flash is about to speed its way past an important mile marker for any TV show: making it to 100 episodes.

In Tuesday’s landmark installment “What’s Past is Prologue,” which was directed by star Tom Cavanagh, Barry/the Flash (Grant Gustin) and his future daughter Nora/XS (Jessica Parker Kennedy) travel back through the show’s timeline in order to collect items they need to defeat season 5’s big bad Cicada (Chris Klein), whose identity they discovered at the end of the last week’s episode.

Image zoom Jeff Weddell/The CW

“In traveling back to the past, they run into a number of what might amount to our greatest hits, if we’ve had any greatest hits at all,” Cavanagh tells EW, explaining that the setup allowed them focus on the season’s plot and celebrate this milestone. “one of the things that we wanted to do with the 100th is that we felt like it’s a benchmark we should honor, but at the same time we didn’t just want to go back through our catalog and say, ‘Hey, look at the cool things that we’ve done over the years.’ I think the challenge for the hundred was trying to figure out a way to hit some of those touch-tones in an organic way and still make the plot immediate and inherent to what we’re doing this season.”

Below, Cavanagh — who previously directed season 3’s “The Once and Future Flash”and season 4’s “Elongated Journey into Night” — previews what we can expect from the episode; from revisiting a heartbreaking moment between Barry and Iris (Candice Patton), to an important father-daughter moment.

Image zoom Jack Rowand/The CW

ENTERTAINMENT WEEKLY: Barry traveled to the future in the first episode you directed, and this time around you’re jumping through the timeline. What was it like having to juggle all of the time periods?

TOM CAVANAGH: First off, it’s fun. This is a comic book essentially and when you open up pages to the comic book, you kind of expect there to be spectacle and entertainment and it vibes away from sort of a procedural bent. I think the people that like the Flash enjoy that. For this one, it was revisiting some of the things that we’ve done, but with a different perspective. What that means practically is you have to recreate some things, you have to invent new things, you have to have new angles, and you have to find ways to incorporate some of the footage that we’ve already used in an organic way from different perspectives.

[With this episode], I think the biggest challenge is, is it good? I think that’s a huge thing people forget some times. Yes, we’re honoring whatever we’re honoring any time a television has to touch on a benchmark, be it a series finale or somebody’s death, or a season finale, but is it good? Is it entertaining? Is it fun to watch? Does it grip you? That was one of the important things — that we tell a clean story that doesn’t complicate things too much, that we don’t try and give too many nods to too many things in the past because we don’t want to muddy up the waters. I think we came up with a very streamlined scrip that has a really good pace and moves along. As we near the end of it, it’s like four or five scenes near the end that could very well be standalone episode-ending [and] season-ending scenes if they wanted to be, and we tend to pile one on after the next. Our last scene is one of the more epic things, because of the content, that we’ve ever shot when you talk about it from a comic book perspective, so it was an honor to be the person putting it on screen.

Was that final scene your favorite part of the episode?

For me, I tend to gravitate toward the smaller stuff, and that’s not to take away from the bigger, larger comic book spectacle, but it’s a look someone will give, a reaction. Just as an actor, I find myself gravitating towards those things that I believe and understand to be deft and subtle — you know, which an explosion isn’t. Watching the people that I know so well and love so much act at the top of their game was probably the most gratifying. There’s so many things that some of the actors on the show don’t necessarily get enough credit for in terms of their abilities because sometimes the spectacle overwhelms everything, but in this instance, we sit with moments.

One of the things I attempted to do — we made a really solid effort at it — was we talked a lot less in this episode; we show a lot more. It’s enjoyable because I think the audience knows these characters very well, and to sit with them and lean into their feelings, as opposed to sit back and listen to what they’re saying, I think in many ways, can be very gratifying, and I think we certainly attempted that in this episode.

How does Nora handle going back through her father’s life, and how does that affect their relationship?

First of all, Jessica Parker Kennedy, who plays Nora, is a gem. She’s just so very talented, and I think she has her own take on the enormity of some of the things she’s witnessing for the first time. I think the biggest compliment I can give an actor when I watch them is that I’m expecting something and they surprise me in a good way. The Barry-Nora storyline was very much an example [of that]. They were very prepared, they were conscientious of who they were as characters, and there’s a number of different elements going on. Nora has her own story that gets revealed, [and] Barry has his reason for doing what he’s doing. Those things are separate, and yet they’re depending on each other, they have to be together.

We took a shot at having this seminal father-daughter moment. It’s one of the highlights, to me, of the show. I’m not going to give away what it is, but the world is falling down around them and they have something beautiful transpire between them, and the two of them were heartbreaking in the best possible sense in this scene. If you put this up before the show comes up, when the viewers watch it, they’ll know it. I don’t know that lesser actors than Jessica Parker Kennedy and Grant Gustin could make us feel what they made us feel in that scene. I’m extremely, extremely proud of both of them. It was a real, real pleasure to watch.

Can you talk about what this 100th episode will say about Barry and Iris’ relationship?

One of the things I like about this episode is we had an opportunity to go and revert to moments before the Barry and Iris that we know now. I think that was a very enjoyable thing to do. I think for both Candice and Grant — you’ll have to ask them the question to get their specific thoughts – there’s a certain innocence, which is fun to be around. Even if it’s not you watching innocence sort of being broken but how someone who is less experienced deals with it, it’s compelling to watch them try to overcome some of the obstacles that they have to overcome. The nicest thing for them is that they did do it together. There’s a couple of very nice sequences here where it’s just the two of them; the world closes off. I spoke to you earlier about trying to take away some of the talking and showing, [and] one of my favorite sequences in this whole thing is basically you’re watching their relationship at an early point from afar, and you don’t really get to hear what they’re saying, but the body language kind of says it all. It’s a difficult moment for them, but what’s lovely about the moment is that as difficult as it is, it becomes quite apparent that they’re tackling it together. They do it so well. There’s something beautiful about it.

Image zoom Jeff Weddell/The CW

In the promo, we saw that you’ll be playing the Thawne version of Harrison Wells again. What was it like revisiting that version of Harrison Wells?

It feels very natural to me. That’s the reason I signed onto the show, so it’s never that far away. Every time I create a new character, the Eobard character is sort of a starting point, a hub of a wheel from which we generate the multitude of other characters. It’s almost as if you started doing one character and as the season progresses you keep jumping back into that suit. It’s just very, very familiar. It just feels very natural. Does that make sense? What I’m saying, there’s no trumpets blaring, there’s no gala music swelling as I step into the suit. It’s like, “Yeah, this is exactly right.”

The promo also includes Savitar and Zoom. Are there any other familiar faces we can expect to see in the episode?

There’s a number of people, and I don’t want to give it away because we tried to be inclusive without making it a list, if that makes sense. There’s certain statements that even if we don’t have an opportunity to meld them into the show itself, we’re referencing them. There’s one sequence that I put together that I think goes as far we can to honor the people that brought us the 100th episode and it’ll be readily apparent when we see it.

When you found out you were directing the 100th episode, did you go back and rewatch old episodes? If so, which ones informed what you wanted to do with it?

I won’t list them all, but everything that we watched I can tell you the intimate details of all of it. There’s 323 [“Finish Line”], 217 [“Flash Back”]. I’m starting to list them, but I really don’t want to list them. There’s no way around it. You have go in and make sure that, “Okay, I can maybe use this, but not use this. Oh, I’m going to change this, going to change that.” The nice thing is when you enter the timeline, things can shift in subtle fashion, and you have certain liberties that you can take; not overt, but you can get in there and be as creative as you can be.

Is there anything else you want to add?

I think one of the nicer things about it is that we’re all kind of, I don’t know if gobsmacked is the right word, but I think everybody appreciates how rare it is. You can go one of two ways: You can feel a sense of entitlement when you’re on a show that doesn’t have the sword of Damocles hanging over and you’re not on the bubble, or you can be like, “Oh man, this is amazing we have this, that we have it with these people no less, that we genuinely like each other.” So much in life is fleeting and I think that you can either approach it as something that is always going to be there, or you can say, “I’m extremely fortunate to have this moment.” I think by and large when we approach our show The Flash, we proceed from gratitude, and getting to triple digits was something that was unexpected and we certainly don’t take for granted. When I’m talking to you because it’s 100, or we have that onslaught of media attention, in a pleasant way, it serves as a reminder of how fortunate we are.

The Flash airs Tuesdays at 8 p.m. on The CW.

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