For several years, DC Entertainment has been trying to build shared universes in movies and on television. The current efforts now include four TV series and three films (with at least two more on the way). Since DC and Warner Bros. are both Time Warner entities, you'd think it would be easy for their various superhero characters to travel freely among series, and even back and forth between the big and small screens -- but that hasn't been the case. Instead, last season's "The Flash"/"Supergirl" team-up was significant, because their two universes were separated not just by a cosmic vibrational frequency, but by the wall between television networks.
As a result, "Supergirl's" subsequent move from CBS to The CW sparked immediate discussions about a four-way crossover involving "Flash," "Arrow," and "Legends of Tomorrow." Moreover, "Supergirl's" producers just announced that Superman would be appearing in the first two episodes of the show's upcoming season -- played by Tyler Hoechlin, and not "Batman v Superman's" Henry Cavill. Both stories raise questions about the strengths of these various barriers, and whether they might allow more audacious team-ups. Today we'll see what rules might govern these crossovers, and what they might permit.
In the past, DC and Warners didn't have much trouble putting out two different adaptations of the same characters at the same time. The Lynda Carter "Wonder Woman" TV series and the Christopher Reeve "Superman" movies ran alongside the animated "Super Friends." Similarly, Brandon Routh starred in 2006's "Superman Returns" while Tom Welling was still going strong on "Smallville"; and the "Batman: Brave and the Bold" animated series contrasted deeply with Christopher Nolan's last couple of Batman movies.
If 2011's "Green Lantern" movie had done better, it might have jump-started its own cinematic universe. Writers Greg Berlanti, Marc Guggenheim and Michael Green turned in a script for "The Flash" which had Ryan Reynolds' Hal Jordan meet Barry Allen in a post-credits sequence.
"GL's" loss turned out to be good for DC's TV fortunes, as Berlanti and Guggenheim joined Andrew Kreisberg on "Arrow"; and the rest is history.
Besides "Flash" and "Legends of Tomorrow," the Arrowverse also includes NBC's "Constantine" and "Supergirl's" parallel Earth. Nevertheless, the Arrowverse stands apart from the other two corners of DC's live-action presence, FOX's "Gotham" and the line of films which started with 2013's "Man of Steel." Looking at the various characters and how they've been adapted for each project, we can start placing them in a few distinct categories.