MAJOR SPOILERS ahead for Crisis on Infinite Earths Parts 4 & 5

Warner Bros. actually requested that Ezra Miller's DC movie version of The Flash appear in the Arrowverse's Crisis on Infinite Earths crossover. The CW's Flash TV show kicked off in 2014 as a spinoff from their flagship Arrowverse series, Arrow, and introduced Grant Gustin's Barry Allen. That same year, Miller was cast as The Flash for Warner Bros. and Zack Snyder's Batman V Superman: Dawn of Justice. Given the concept of the multiverse is well-established within DC Comics, fans clamored for Gustin and Miller's Flash heroes to crossover at some point, especially since both characters have been well received in their respective properties.

The CW's Arrowverse finally made the fans' wish come true last night in Crisis on Infinite Earths when Miller's DC movie Flash appeared in a scene alongside Gustin's Barry Allen. During Part 4, when the Arrowverse's Barry must use memories and connections to his friends to find them within the Speed Force, he runs across the DC movie Flash. It's a short scene, only lasting about 90 seconds, but it has major implications for both the Arrowverse and DC movie Flash characters. Now, Arrowverse executive producer Marc Guggenheim reveals how this major cameo came together - and whose idea it was.

Related: Arrowverse's New Multiverse Revealed: Which Shows Are On What Earths

In an interview with Variety about the Crisis on Infinite Earths two-part finale, Guggenheim was asked about how they were able to combine the DC TV and movie worlds. After they'd already wrapped filming on Crisis on Infinite Earths, Guggenheim said, "I got a phone call from [Warner Bros. boss] Peter Roth saying, 'I know you’re locked, but can you put Ezra into the crossover?' And I said, 'Yes.'" Roth was apparently skeptical that Guggenheim could fit the DC movie Flash into the crossover, to which the Arrowverse producer said, "Yeah, I know, but if you’re telling me Ezra Miller can be in the crossover, I can make it happen." Guggenheim went on to explain:

I called Eric Wallace who is the showrunner of Flash, and he called up Grant Gustin - because the one thing that was our only concern was the thought we didn’t want to do it unless Grant was 100 percent on-board with it. And he was. He was incredibly enthusiastic and on-board with it. And then we got on the phone with Ezra Miller and told him the scene I had written and he was completely into it. And we just went. We put together a unit of the Flash crew on the Flash set [since Arrow’s team, which had produced the rest of the hour, was gone]. And much to our surprise, no one noticed Ezra Miller was in Vancouver and no one leaked it from the crew, which we appreciate. So we were able to keep it a surprise.

Both the Arrowverse and DCEU Flashes meet in Crisis On Infinite Earths

In this day and age of superhero movies and TV, where unofficial set photos can reveal everything from first looks at costumes to surprise cameos, the fact that Guggenheim and The Flash crew were able to keep Miller's scene a secret is nothing short of a miracle. Even Supergirl actress Melissa Benoist revealed she didn't know about the cameo until the episode aired when she commented on Gustin's behind-the-scenes photos with Miller on the Crisis on Infinite Earths set. Guggenheim's explanation of how the scene came together offers insight into why no one else knew, since it was such a small shoot and none of the other Arrowverse actors were involved beyond Gustin.

What's perhaps most curious about Miller's Crisis on Infinite Earths cameo, though, is that Warner Bros. requested it be included in the crossover. There's been a notorious distance between DC TV shows and the movies. One example was when the Arrowverse wanted to use Harley Quinn, but couldn't because the movies planned to use the character for 2016's Suicide Squad. However, that distance has seemingly changed given Warner Bros. asked the Arrowverse to feature Miller's Flash. It also presumably works as setup for The Flash movie slated to release in 2022. Without this cameo (and if the movie doesn't move from that date), it would be almost five years between Miller's last appearance as The Flash in Justice League and his solo movie. So this cameo can not only bridge the gap between the Arrowverse and the DC movies, it offers a tease for what's to come on Warner Bros' DC film release slate.

Next: All 28 Upcoming & In-Development DC Films

Source: Variety

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