Producer Greg Berlanti is the mastermind behind DC's shared television universe, including Arrow, The Flash, and Legends of Tomorrow. Berlanti also produces Supergirl, which continues to dazzle fans every week with the adventures of Kryptonian Kara Zor-El in National City. Since fans learned that Berlanti would produce Supergirl, speculation about a potential crossover with the Arrow/Flash universe has only grown.
Producers have discussed the possibilities of a crossover before, but we haven't seen much headway. Being on a separate network (CBS) from the Arrowverse (CW), it's possible that Supergirl may continue without a direct connection, but maybe not.
Bleeding Cool reports that The Flash and Supergirl may crossover before next year's May sweeps week, though this plan hinges on CBS ordering more episodes of Supergirl. The show is commissioned for 13 episodes, but CBS reserves the option to increase that to 22 episodes. If this happens, we may see the Flash and the STAR Labs crew join Supergirl in National City.
According to Bleeding Cool, CBS thinks Supergirl could do with a ratings boost. Ratings for the pilot episode were strong, but the show has dipped since then. Crossover episodes have almost always boosted the ratings of The Flash and Arrow, so it would make sense that CBS could consider a crossover to boost the ratings of Supergirl.
Tonally, Flash is the perfect superhero to crossover with Supergirl. Both shows support a light-hearted tone, as opposed to the darker Arrow. But then there's the question of continuity. Superman appears to have been established in Supergirl's world for many years, yet there's no mention of him (or her) in the Arrowverse. Berlanti and the other creators may have to retcon the story to fit the shows together, but that wouldn't be very hard, considering Flash has been toying with alternate timelines recently.
Hopefully, Supergirl will get her 22 episodes and we can all look forward to seeing this rumor unfold. The DC TV universe has yielded a lot of success for the CW, and it will most likely continue to evolve and develop as time moves on. We can look forward to more DC characters, and we can certainly look forward to more Supergirl.
Supergirl continues next Monday @8pm with “Red Faced” on CBS.