Who is the new Batman? What's next for Supergirl? Everything you need to know about the ending of 'The Flash' (spoilers)

Warning: This post contains big spoilers for The Flash

After The Flash, the DC Extended Universe will never be the same... or will it? The long-delayed solo adventure for DC's resident Scarlet Speedster (played by Ezra Miller) has finally raced into theaters as a swan song for the Snyderverse — the version of the DCEU that launched in 2013 with Zack Snyder's Man of Steel — and a herald for the yet-to-debut Gunnverse, overseen by new DC Studios heads, James Gunn and Peter Safran.

But those aren't the only two universes at play in The Flash: the film's time-traveling story combines multiple multiverses featuring previous screen versions of some of DC's biggest heroes. The most obvious one, of course, is Michael Keaton, who returns to the Batsuit for the first time since 1992's Batman Returns. After starting a new branch of continuity where Krypton's General Zod is about to conquer a Superman-free Earth, Barry Allen teams up with Batman, Supergirl (Sasha Calle) and another Barry, also played by Miller.

But as the film's final scene reveals, Keaton isn't the last Batman standing. That last beat is one of the many surprise twists in the Andy Muschietti-directed film. Here's Yahoo Entertainment's guide to the big reveals in The Flash, and what they mean for the future of the DCEU.

Who's the Batman now?

Well, it certainly ain't Ben Affleck. The DCEU's current Batman has made it clear that he's retiring the character after his appearance in The Flash. (Affleck reportedly filmed a cameo for December's Aquaman and the Lost Kingdom, but that scene may have been cut from the Jason Momoa sequel.) For the record, it's likely not Keaton either. The Beetlejuice star was supposed to cement his return to the cowl with follow-up cameos in Aquaman 2 and Batgirl, but his Aquaman pop-up was deep-sixed in favor of Affleck's discarded appearance, while Batgirl was deep-sixed altogether.

Now we can see why he hit the cutting room floor: Keaton's Batman perishes in The Flash's climactic battle with General Zod (Michael Shannon), and no matter how many times they reset the timeline, the two Flashes can't save him. Ultimately, that repeated failure teaches the Barrys a valuable lesson: Sometimes you can't change a person's destiny — even if that person is Batman.

After resetting the timeline and returning to his reality, Barry reconnects with Bruce Wayne, who drives up to meet him. But when the car door opens, out steps... George Clooney, who previously played the Caped Crusader in Joel Schumacher's franchise-killing 1997 flop, Batman & Robin. The ER star has long blamed himself — semi-jokingly, of course — for "destroying the franchise," and has often claimed he'd never play Batman again. And that's technically still true, since Clooney never puts on the cape and cowl during his brief Flash appearance.

Don't expect the return of Clooney's notorious Bat-nipple suit either. The actor's appearance in The Flash is very clearly a last laugh instead of a harbinger of things to come. James Gunn has said as much on Twitter, and the search is currently underway for the actor who will be playing Bruce and Batman in The Brave and the Bold — the Muschietti-directed Batman-centric entry in Gunn's "Gods and Monsters" storyline for the new DC Universe that will pair the Dark Knight with his son, Damien Wayne, aka Robin.

Meanwhile, Robert Pattinson will continue to defend Gotham City in Matt Reeves's corner of the wider Bat-verse, which will continue in the Max series, The Penguin, as well as The Batman 2. Sorry, George — maybe you can get that Peacemaker reboot off the ground, instead.

Does Henry Cavill return as Superman?

For a brief moment, the Man of Steel star seemed to have a second act as Superman, making a surprise appearance at the end of Black Adam. Cavill also reportedly filmed a cameo for The Flash alongside former Justice Leaguers Affleck and Gal Gadot, but that appearance didn't make it into the final cut, where his Superman is referred to but never seen. (Gadot, on the other hand, does make what could be her final DCEU appearance; Wonder Woman currently hasn't been announced as a part of the "Gods and Monsters" story, and the actress has since rejoined the Fast and Furious universe.)

Instead of Cavill, the returning Superman we do see is none other than Christopher Reeve, who played the Man of Steel in four films released between 1978 and 1987. The actor died in 2004, and appears in the climax of The Flash as a digital stand-in, one who looks on from his reality as the two Barrys nearly cause a crisis across infinite Earths. It's not unlike the way that Rogue One brought back Peter Cushing's Grand Moff Tarkin and Ghostbusters: Afterlife resurrected Harold Ramis's Egon Spengler.

And that's not all: Reeve's Superman is joined on his Earth by a digital avatar of Helen Slater's Supergirl from the 1984 spin-off — a team-up that never happened in our reality. Meanwhile, a neighboring Earth features George Reeves in his Superman garb from the black-and-white ’50s TV series.

Using digital technology to bring back late actors is a controversial subject, and Reeve's appearance has already stoked a social media debate over the appropriateness of these kinds of cameos. It's a question that won't be settled by The Flash, so aging superheroes like Keaton may want to leave specific instructions for his next of kin in terms of how long he wants his Batman to outlive him.

Is Nicolas Cage a Man of Steel?

Nicolas Cage's Superman lives! Back in the ’90s, the eccentric thespian very nearly played the Last Son of Krypton in Tim Burton's abandoned Superman adventure, Superman Lives, penned by Kevin Smith. "It would have been beautiful," Cage told Yahoo Entertainment in 2017. "Tim and I were about to get up to something really relevant."

The Flash finally awards Cage the chance to live out that beautiful dream, with his long-haired Superman appearing alongside Reeve and Reeves in the movie's climax. And like those dearly departed actors, the still-living Cage doesn't appear in the flesh. Instead, he's another digital creation, de-aged to look as he did in the Superman Lives test footage. In a nice touch, Cage's Superman is seen fighting a giant spider — something that Smith was specifically told to include in his script by arachnid-obsessed producer Jon Peters.

What's next for Supergirl?

Gunn has already said that one of the 10 projects that compromise "Gods and Monsters" will be Supergirl: Woman of Tomorrow, a movie version of a comics storyline that originated with writer Tom King and artist Bilquis Evely. "She was on a piece of Krypton that drifted away from the planet and she lived there for the first 14 years of her life," Gunn says of how that film will establish a "harsher" version of Superman's Kryptonian cousin. "[She was] in a horrible situation where she watched everyone around her die."

The version of Supergirl that Calle plays in The Flash is pretty harsh as well, going after Zod with extreme prejudice for finding and killing Kal-El while the infant is still in transit to Earth. But like Keaton's Batman, Calle's Supergirl doesn't survive that battle in any of the realities that the Barrys generate. That suggests that she won't be returning for "Gods and Monsters," but Calle is holding out hope for a reprieve.

"I hope to continue playing Supergirl," the actress told Entertainment Weekly. "I love her deeply! And I think that [The Flash] is really a runway to a bigger story for her. Supergirl: Woman of Tomorrow, by Tom King, is an incredible comic. I love it. I think it's so cool."

Is there a post-credits scene?

To keep audiences hydrated for Aquaman and the Lost Kingdom, Momoa's Arthur Curry shares a drunken night out with Miller's Barry in an after-the-credits sequence. Well, Arthur is drunk at least — Barry is too busy describing his multiverse adventures to Aquaman to imbibe much brew. While there's no overt Lost Kingdom setup in this particular scene, it's a friendly reminder that what's widely presumed to be the final Snyderverse movie is only months away from release. Catch the wave!

The Flash is currently playing in theaters now