Fresh off her debut season over at CBS, "Supergirl" is headed to The CW, and big things are happening for National City's resident Girl of Steel. For one, her famous cousin Superman will be showing his face (finally!) -- and that's not to mention the slew of other DC Comics characters that will show up for "Supergirl's" sophomore season. In anticipation for "Supergirl's" unprecedented inter-network move this fall, CBR breaks down everything we know (so far) to prepare you for Kara Danvers' next outing.

9 "Supergirl" Crashes The CW



Alright, let's get the big one out of the way first. Though helmed by executive producers Greg Berlanti and Andrew Kreisberg, "Supergirl" Season 1 debuted on CBS, away from their slate of superhero shows on The CW -- but all that is about to change.

In May, news broke that The CW had picked up "Supergirl" for Season 2. Thanks to the move, "Supergirl" will join her superhero compatriots "Arrow," "The Flash" and "DC's Legends of Tomorrow," all of which also air on The CW. Earlier in the year, "Supergirl" crossed over with "The Flash," scoring a 2.5 rating in the 18-49 demographic and 9.6 million total viewers in L+7; it seems like there will be more potential for similar crossovers thanks to the network shift. Despite the move, however, "Supergirl" will stick to the same timeslot, airing Mondays at 8 pm EST.

Of course, that doesn't mean CBS was looking to drop the show altogether. "The ratings did start a little higher and they came down a bit," CBS president Glenn Geller said shortly after the announcement. "I think it found the right home. It's a win-win for us. We co-own the CW and we made a great deal with Warner Bros... Who's to say if we hadn't made that deal that we wouldn't have picked it up." CBS Corporation presidsent and CEO Les Moonves also revealed that they would've considered picking up "Supergirl" for a sophomore season, had the CW deal not gone through.

Of course, "Supergirl's" unprecedented move has opened up a whole new world of questions. Does this mean there will be more inter-show crossovers? How will it impact the cast? We at CBR have considered all this and more, though we don't have all the answers just yet.

8 Superman Steps Out of the Shadows



In "Supergirl" Season 1, Superman largely stayed out of Supergirl's way -- and for good reason. As recently as April, executive producer Ali Adler revealed that Superman hadn't fully appeared on the show because "right now, we're just telling Supergirl's story. We'll see where that takes us." However, now that Supergirl has established herself as a hero in her own right, Superman (and Clark Kent) will return The CW in "Supergirl's" sophomore season.

That isn't to say Superman has been entirely absent from the show. He did show up occasionally, but his face was always obscured or hidden by trick camera angles, which left casting for the character wide open. The honor finally went to "Teen Wolf" star Tyler Hoechlin, who appear in the beginning of the season for an as-yet-unannounced number of episodes.

"I think the fun is going to be finding where Clark Kent is in this world. I'm just excited to find out Clark's sense of humor," Hoechlin said of the character.

The addition of Superman to "Supergirl" marks the first time we've seen the character on the small screen since Tom Welling's portrayal in "Smallville." While some fans hoped Welling would return to don the cape on "Supergirl," don't count him out of the show quite yet. CBS dropped his recent "Section 13" pilot, which may leave him open for a role on "Supergirl" in the vein of Helen Slater's Eliza Danvers or Dean Cain's Jeremiah Danvers.

7 President Lynda Carter



In March, Berlanti and Kreisberg revealed that they had courted "Wonder Woman" star Lynda Carter for a role on "Supergirl." However, due to scheduling conflicts, they were unable to squeeze her in -- until now.

Carter will play the President of the United States in "Supergirl" Season 2. She's slated to appear in multiple episodes, starting with the third installment of the second season, which will likely air in late October. No further details about the role have yet been released.

Carter starred as Wonder Woman/Diana Prince for three seasons between 1975 and 1979, a role that stands as one of the most iconic live-action performances of a comic book superhero. She'll follow in the footsteps of DC Comics veterans like Helen Slater (1984's "Supergirl"), Dean Cain ("Lois and Clark") and Laura Vandervoort ("Smallville"), all of whom have also appeared in "Supergirl."

6 A Growing Cast



When "Supergirl" returns for its sophomore season, National City is going to feel a lot more crowded. In addition to Superman's impending arrival, the show is reportedly seeking to cast five major new additions, including Lex Luthor's sister, a metahuman detective named Maggie and more.

According to the report,

Lena Luthor, who will be in the 25-35 year old range, arrives in town to get out from under the shadow of her infamous brother. She's described as sexy and smart and determined to get what she wants.

Newcomer Nick Farrow will be a "brash leading man" and the son of a famous reporter who rivals Kara at CatCo. The report describes Nick as "looking to make a name for himself in the news world but the question of whether he can leave behind his former selfish and hedonistic ways will constantly arise. In hanging out with Kara, the hero in Nick might finally come out."

The casting also includes three additional characters, including:

...The Doctor, the diabolical female leader of Project Cadmus who uses her surgical skills to implant prisoners with alien technology (and who sounds a lot like Sterling Roquette); Snapper Carr, a veteran journalist appointed by Cat to remake the news division by going old school (not to be confused with the Justice League sidekick); and the comics-inspired Maggie, an out and proud detective for the newly formed Science Police, which deals specifically with metahuman and alien threats.

With characters like The Doctor, it appears that "Supergirl" will explore Project Cadmus, as was implied in the show's debut season when J'onn learned that Jeremiah Danvers was not only alive, but being held there. Additionally, Maggie sounds a lot like Maggie Sawyer, who -- in the comics -- was Batwoman's girlfriend and a prominent member of the Gotham City Police Department.

5 Here Comes Cadmus Labs



Speaking of Cadmus Labs, the mysterious organization will loom large over "Supergirl" Season 2, particularly where Kara discovered that her foster father Jeremiah Danvers was not only alive, but being held captive there.

"It's going to remain more of an evil, specter-y thing that's out there, but it's definitely something that we're going to pursue," Kreisberg shared. "You know, Cadmus has such a rich history in the comics and the animated shows. There's so much there to mine. It'll definitely be part of Season 2."

Fans familiar with the DC Universe will recognize Cadmus Labs as the organization that successfully combined Superman and Lex Luthor's DNA to create Superboy. If you have any doubts about cloning technology in the "Supergirl" universe, make sure you check out the TVs behind Cat Grant in her office; the screens often contain Easter eggs, and the show has recently begun teasing burgeoning cloning tech.

4 Mysterious Kryptonian Spaceship



Cadmus Labs isn't the only Season 1 mystery hanging over Season 2. In the Season 1 finale, Kara had a close encounter with a crashed Kryptonian spaceship much like her own, but who -- or what -- is inside is yet to be seen. It's a secret that's being kept under lock and key, so much so that even Melissa Benoist doesn't know the answer.

"I've heard a few rumblings of who it might be," she said at The CW's upfront event.

While this mystery likely won't be solved until the Season 2 premiere this fall, we at CBR have a few guesses as to the identity of the of this mystery alien.

3 The Many Loves of Kara Danvers



When "The Flash's" Barry crossed over into Kara Danvers' world for an episode of "Supergirl," the two had instant chemistry. From superpowered trips to the ice cream store to a race (of course), the two became fast friends over the course of the one-off story. Naturally, fans saw the budding of a romantic relationship between the two, and star Grant Gustin would tend to agree.

"It would be a good match," he said.

But not so fast, Grant! Benoist isn't too sold on the idea. "I don't know that they'd ever get together," she shared. "I think they're too similar... I think they're pals, pigging out on ice cream."

While an inter-dimensional relationship would certainly be difficult to maintain, "Supergirl" has made the jump from CBS to The CW for its second season, so that situation could very well change. Either way, the Girl of Steel will likely make her way into The CW's annual "Arrow"-verse crossover, so it wouldn't be entirely out of the question for the two to develop romantic feelings for one another.

As it is, Benoist isn't too sure about Kara's romantic future with Mehcad Brooks' Jimmy Olsen. "That is up in the air," she said at The CW's upfront event. "What I love about Kara is about naive and innocent she is about love. Whatever happens, it will be funny and awkward and great."

2 Kara's (Possible) Earth-1 Doppelganger



"The Flash" Season 2 introduced parallel earths to the "Arrow"-verse and confirmed the existence of alternate world doppelgangers by proxy. While we've gotten to see a few of Team Flash's doppelgangers, we haven't met any doppelgangers for the protagonists of other DCTV shows -- but that could change.

Asked if Earth-1's Supergirl will swing by "The Flash" sometime soon, Kreisberg said, "Any Kara that exists on Earth-1 would also have to have been an alien. It can't just be Kara Danvers from Poughkeepsie."

"Different costume, but sure," he added. Though he didn't quite confirm the existence of Earth-1's Supergirl, his addendum about her costume is important to note; after all, Power Girl -- widely recognizable for her white costume with a cleavage-bearing chest hole -- is an alternate world version of Kara Zor-El in the comics.

Berlanti also weighed in on whether or not Barry Allen has a doppelganger on Supergirl's Earth. "We just talked about that recently," he said in March. "There is room [for that], absolutely."

1 The Big Crossover



With "Supergirl" joining "Arrow," "The Flash" and "DC's Legends of Tomorrow" on the network next season -- all shows under the purview of executive producer Greg Berlanti -- the time is ripe for a massive crossover of all four shows, and "Arrow" star Stephen Amell predicts that the superhero team-up will air across one single week as a four-night extravaganza.

"I think what we'll end up seeing is one giant four-night crossover. This is kind of an unprecedented moment in terms of the history of network television. To have four shows [with the] same showrunner," he explained, referring to Berlanti.

The CW president Mark Pedowitz would tend to agree with that. "Our annual crossover event this fall [will] be the biggest one ever," he shared.

However, Amell draws the line at a musical crossover: "No. I'm out! I'm the first one. I get to draw the line, and I draw the line at musical."

Meanwhile, "Legends" star Brandon Routh wants a smaller scale crossover -- for himself. "I hope to be on 'Arrow,' 'Flash,' and 'Supergirl'... make the trifecta!" he said, adding, "I wish ['Supergirl's' Superman Tyler Hoechlin] the best and hope to meet him if Ray gets to crossover to 'Supergirl!'"

Starring Melissa Benoist, Calista Flockhart, David Harewood and Chyler Leigh, "Supergirl" will debut Monday, October 10 at 8 pm EST on The CW.