'The Flash' And 'Supergirl' Crossover Confirmed By CBS And The CW; How Will The Heroes Team Up?

As the DC Comics TV universe continues to expand, two of its most popular heroes will finally pair together, no matter what network they happen to be on at the time. It’s been announced that the speedster from the CW and the Girl of Steel from CBS will finally join forces for a crossover adventure later this year.

The two parent networks announced the news on Feb. 3 that Grant Gustin of “The Flash” will bring his version of Barry Allen to the March 28 episode of “Supergirl,” marking the first cross-network team up for both characters since their shows aired. “Supergirl" is currently in the middle of its first season and “The Flash” just began the back half of its second season.

“We are so incredibly excited to announce something that we have dreamed of happening since we starting making Supergirl,” Greg Berlanti and Andrew Kreisberg, who are executive producers on both series, said in a statement. “We want to thank Grant Gustin for making the time to come visit (on top of his already immense workload) and all of the folks at CBS, The CW, Warner Bros. and DC for working this out.

Previously, Berlanti mentioned at the Television Critics Association press tour that a crossover between the two shows, which have most of the same creative teams working on them, was plausible. However, he warned it would require a lot of behind-the-scenes dealing since the characters exist on different networks. Interestingly enough, demand for this specific crossover began in May 2015 when the heroes posed together, in costume, on the cover of Variety. Now it seems everything came together sooner than expected and Kara Danvers (Melissa Benoist) will get a little backup from the world’s fastest man.

While it’s certainly exciting for “The Flash” and “Supergirl” to team up, many fans may be wondering what the canon implications on both shows will be. “The Flash,” and by extension “Arrow” and “Legends of Tomorrow,” exist in a world that’s never mentioned the existence of aliens, Metropolis, National City or Superman — all of which play key roles in “Supergirl.” Luckily, fans of the CW series might not have to educate themselves on the intricacies of the CBS universe as “The Flash” has a built-in plot device that lets him travel between parallel universes. While it would be a little bit of a cheat, Barry Allen could simply find himself in a version of Earth that plays home to Supergirl and her mythos.

Diehard fans of the DC Comics TV universe will note that this isn’t the first time the CW has reached across networks to bring in some key characters from the source material. After NBC canceled its failed adaptation of “Constantine,” Stephen Amell of “Arrow” championed on behalf of the show’s cult following to bring Constantine (Matt Ryan) in for a guest role in Season 4. As a result, following the “Flash”/”Supergirl” crossover, the shows that exist in the same universe will include: “Arrow,” “The Flash,” “Legends of Tomorrow,” "Constantine" and “Supergirl.”