Everything We Know About the Arrowverse 'Crisis' Crossover: 'Kingdom Come,' Burt Ward, Anti-Monitor and More!

While Marvel Studios was dominating San Diego Comic-Con with talk of its next phase of film and television projects, another superhero universe was setting the stage for its most ambitious crossover yet, and it looks every bit as exciting.

Long-time comic book fans know that "Crisis on Infinite Earths" is essentially the Holy Grail of superhero crossover comics. Published in 1985 by DC Comics, it collapsed the DC multiverse into one single universe (for awhile) and saw the deaths of scores of superheroes as they battled the forces of the Anti-Monitor.

The CW's Arrowverse of shows has been setting the stage for their own "Crisis" for years now, first hinted at in "The Flash" series premiere. As that show heads into its fifth season, it will speed headlong into the network's "Crisis on Infinite Earths," the network's biggest crossover event yet incorporating "The Flash," "Supergirl," "DC's Legends of Tomorrow," the final season of "Arrow" and the debut season of "Batwoman."

And unlike events of the past few years, this one won't be resolved in a single block of episodes in a single week. Instead, the five-part saga will take place across the winter hiatus with three episodes book-ending the 2019 chapters in December and two kicking off in January 2020. It's all-but-confirmed one of the 2020 episodes will be the season premiere of "DC's Legends of Tomorrow," but the schedules for the remaining shows remains murky.

Here's everything we know (and think we know) about The CW's most ambitious event yet (plus teaser trailers for four of the five shows below):

The original comic book "Crisis on Infinite Earths" was a threat to the DC multiverse, and it promised that many Earths would die. To that point, the publisher's various comic book lines had existed on separate earths that would cross over occasionally for exciting stories. Sound familiar?

By the end of the 12-part publishing event, the DC Universe would be a single universe with many, many casualties along the way. Many Earths died and many heroes died, while many others merged into a new single continuity on a single Earth. Could the CW be planning something similar so that "Supergirl" and "Batwoman" shift over to join the rest of The CW shows in the same reality?

Or perhaps this "Crisis" will end differently and all the shows will continue to live on in parallel realities, including "Black Lightning," which is apparently in such a reality of its own it won't even be participating ... unless that is The CW's biggest surprise they're keeping close to their chest.

Arrowverse producer Marc Guggenheim promised Comic-Con fans that this "Crisis" will at least kick off in the same deadly way as the comic series. "We're going to begin the way 'Crisis on Infinite Earths' the comic begins, which is the destruction of various parallel universes," he told ComicBook.com. "And the goal is for us to adapt key moments from the comic, those seminal moments."

After dropping the bombshell that Brandon Routh would be returning the blue and red tights of the role he made famous in the film "Superman Returns" -- with a twist -- "Batwoman" executive producer Caroline Dries promised, "We've got a ton, a ton, a ton of characters coming into the five-part event."

Even Routh's Superman is technically a new character as he won't be reprising the Richard Donner version of the character he revived for the film. Instead, he'll be taking on the classic "Elseworlds" version of the character presented in the classic 1990s "Kingdom Come" mini-series, which featured older versions of DC's classic characters in a dark future where the next generation takes vigilante justice too far.

He will presumably come face to face with Tyler Hoechlin's Superman (who has appeared sporadically in "Supergirl" since Season 2). This version is also expected to return from his adventures off Earth at some point during the next season either before or during the epic crossover events. Maybe he'll bring Lois Lane back with him so she can chronicle all this craziness.

Perhaps one of those biggest surprises is the inclusion of Burt Ward, who famously portrayed the wise-cracking Robin in the 1960s "Batman" television series known for on-screen sound effects and campy dialogue between Ward and Adam West as the Caped Crusader. The show's lighter tone would change the direction of the Batman character for years until Tim Burton cast Michael Keaton in the much darker 1989 film.

It's unclear if Ward will be portraying an older Robin, or perhaps someone who'd taken over the mantle of Batman, or a new iteration of his characters entirely, as Routh is. It's also possible he's just a bit of nostalgia stunt casting and he'll be taking on an entirely new role.

Also returning to the fold for the crossover event is Jon Cryer's well-received Lex Luthor, who surprised fans with his dark turn on "Supergirl" last season. "Crisis" fans know that a version of Lex, Alexandor Luthor, played a pivotal role in the original series, but it's unclear if Cryer's version will have anything to do with that character or even be the same Luthor seen on "Supergirl." Parallel Earths and all that.

By now, everyone knows that the Monitor came calling during the shocking season finale of "Arrow" to collect on the promise Oliver made during last season's "Elseworlds" crossover event. But some casting news to come out of Comic-Con makes his final-season journey a little more murky than first imagined.

In particular, the inclusion of two actors who portrayed characters who have been long dead on the veteran CW series: Colin Donnell and Josh Segarra, who portrayed Oliver's one-time best friend Tommy Merlyn and Adrian Chase, respectively. With just a 10-episode final run, "Arrow" is expected to run directly into the "Crisis on Infinite Earths" crossover and only come out the other side with two episodes left ... though what state it's in by then is anyone's guess.

In the season finale, Oliver was reminded of his promise to do "whatever the multiverse requires to survive the crisis that is looming," and then plucked out of his life with Felicity and their child for a suicide mission to save Barry (Flash) and Kara (Supergirl) from their own grisly fates in the looming threat. A flash-forward teases that he was successful, leaving many fans scratching their heads as to what happens now?

"Arrow" may look like an entirely different beast in its final shortened season, as Arrow journeys with The Monitor to try and prepare for and/or prevent the inevitable "Crisis." We already know parallel Earths are in play, and now with glimpses of friends and enemies long dead perhaps time travel is as well. Either way, "Arrow" looks to be a very interesting show this fall and an essential lead-up to "Crisis."

Additional casting for "Arrow's" final season indicates the importance of the flash-forward sequence fans were treated to in the final moments of the Season 7 finale. Oliver Queen may have died in 2019 (is it preventable?), but his legacy clearly lives on. No less than four actors from that flash-forward have been upped to series regulars for the final season, indicating just how prominent they will be.

This means that either we will be spending a lot of time in 2040 or that these future freedom fighters will be making their way back to 2019 ... or possible a bit of both. Leading the charge will be Charlie Barnett as John Diggle Jr., a character not yet seen but mentioned as the leader of the Deathstroke gang in the future.

Viewers "are going to be really surprised about the way we bring him in," said executive producer Marc Guggenheim. "And particularly what costume he wears."

He's joined by his adopted brother Connor Hawke (another Green Arrow in DC continuity), played by Joseph David-Jones, as well as the now-adult chilrden of Oliver and Felicity, Mia Smoak (Katherine McNamara) and William Clayton (Ben Lewis).

You can't have a "Crisis on Infinite Earths" without the Anti-Monitor and it looks like The CW won't have to. And they didn't even have to look very far to find him, as LaMonica Garrett will be taking on the role. Fans have already gotten used to Garrett's visage and distinctive voice as the Monitor, brother to the Anti-Monitor and supposed force for good.

Now, he'll play the opposite side of the same coin as well, as the force of destruction seeking to tear asunder the entire multiverse. And for fans worried that The CW will destroy the Anti-Monitor's iconic look, they needn't fear. Yes, he's recognizable as Garrett, but he also looks a lot like his comic book counterpart in the concept sketch Marc Guggenheim shared.

In another bit of double-billing, "The Flash" veteran Tom Cavanagh will take on the role of the saddest person in the DC Multiverse, the immortal Pariah. First glimpsed throughout the original "Crisis on Infinite Earths" event in the mid-1980s, Pariah would appear as world were about to die, cursed to witness their final moments as penance for past misdeeds.

According to new "Flash" showrunner Eric Wallace, Pariah will emerge as a result of the first half-season arc of the show, which focuses on new villain Bloodwork, played by "Heroes" alum Sendhil Ramamurthy. That storyline sets the stage for the entire "Crisis" event.

Now we just need a Harbinger to help bring the heroes together to face this threat. At least, that was a significant character in the original "Crisis" event who worked with her father -- and then (uh-oh!) -- in the early days of the "Crisis" to assemble the right heroes from across the multiverse to battle the Anti-Monitor. Of course, the Monitor has been doing a lot of his own heavy lifting, so the may just skip this character.

In countless Crises in DC Universe history, there has always been a Flash at the center of it. In many cases, that Flash has had to die. But it all began with Barry Allen sacrificing himself to save the universe in the original "Crisis on Infinite Earths." This created a precedent and proved to be one of the most monumental changes in DC Comics, as Wally West took over the mantle for many years to come until another Crisis-level event brought Barry back.

Foreshadowing for this possible fate for The CW's Barry Allen will be set up in the Fall when the Monitor returns and "says the universe is in danger and the only way to save it is for Barry to sacrifice himself," according to "Flash" star Grant Gustin. "It's tough hearing you're supposed to die."

Fans hoping that Arrow's deal with the Monitor during last season's "Elseworlds" event would replace the threat of doom for Barry were apparently a little too optimistic. It's just not a "Crisis" without a Flash's life on the line!

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