[Warning: The following contains spoilers from Monday's Supergirl. Read at your own risk!]

Kara (Melissa Benoist) is facing many changes on Supergirl this season while also losing some of the most important members of her support system as the pressure of being National City's superhero increases.

Superman (Tyler Hoechlin) has officially wrapped up his first visit to National City, but he wasn't the only person leaving Kara by the end of "The Last Children of Krypton." The episode dropped the (admittedly foreshadowed) bomb that Cat Grant (Calista Flockhart) would be leaving CatCo Media -- and the show -- for a new adventure. Her departure comes just as Project Cadmus announced they would be waging war against all alien visitors to Earth.

TVGuide.com attended a small press screening of the episode where executive producer Andrew Kreisberg broke down some of the big changes coming for Kara and where Supergirl is heading in its sophomore season.

Melissa Benoist and Chyler Leigh, <em>Supergirl</em>Melissa Benoist and Chyler Leigh, Supergirl


On Cat Grant's departure

One of the biggest changes for Kara this season will be the departure of her boss and mentor, Cat Grant. Actress Calista Flockhart decided to take on a smaller role in the show's second season after production moved from Los Angeles to Vancouver to lower costs. Cat has not only delivered some of the best one-liners on the show, but has also been a great source of strength for Kara.

Addressing concerns that the show would lose some of its feminist edge without Cat's infamous empowering monologues, Kreisberg not only noted they're hoping Flockhart will be able to return in the future, but that the series doesn't necessarily need Cat to continue marching on.

"That's the biggest feminist statement that we could make, that [Kara] -- especially when you compare [Supergirl] to our other shows like Flash and Arrow -- there's nothing she goes up against that they don't go up against. She's just as valorous, just as confident, just as emotional, just as flawed and just as strong as any of the other male heroes that we've created," Kreisberg said.

While Kara can carry the feminist torch on her own, Cat grant will need to return to National City eventually if only to answer one burning question: Does Cat know that Kara Danvers is Supergirl? "I love how Calista plays it where you're never quite sure [if she knows]," Kreisberg said. "She plays it so that if you decided to have her, at the end of any episode, go 'I've known you were Supergirl the whole time,' you could look back at those little moments and go 'Oh, you know what? The way she looked at her there or the way she said that, I bet she did know the whole time.'"

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On Superman returning to Metropolis

Cat's departure comes on top of Kara losing her new (favorite?) crime-fighting partner to his own city. The show legally can't have Superman as a regular on the series, but in the span of two episodes, Clark and Kara have become extremely close. Kara officially knows what it's like to fight side by side with her cousin and have someone close by that knows what it's like to be lone Kryptonians on Earth.

Luckily, Kara and Clark will continue to stay in contact via text message until Superman can return to the show. "While the first season we couldn't show Superman, [the text messages] were our best attempt to show that [connection]," Kreisberg explained. That groundwork will make the Kara and Clark long-distance conversations even more powerful now that the audience has met Superman.

"Those scenes always had a lot of strangely strong resonance even though they were a gimmick," Kreisberg continued. "Now that Tyler has inhabited the part and casts a long shadow, whenever there's discussion about Superman in subsequent episodes, or the thought of them talking to each other, or somebody says 'I'll check in with Superman', now you can imagine Tyler so it makes all of those mentions and the idea of him being out there that much more powerful because you can imagine [him]. You know that he's out there and he's ready to help."

Of course, Supergirl also hopes to bring Superman back in the future, but it remains to be seen when that will happen.

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On Project Cadmus

It appears that the new big bad for Season 2 is Project Cadmus, the secretive government organization that performs dangerous experiments on aliens and has now announced they are waging war on all extra-terrestrial life hanging out on Earth. They made a good attempt at trying to take out Supergirl and Superman this week, but we know they aren't done yet.

More importantly, Project Cadmus also has Jeremiah Danvers (Dean Cain), and no one is sure what state he will be in when Kara and Alex (Chyler Leigh) eventually find him. Kreisberg teased it would be a big surprise, but wasn't willing to give too much away just yet.

"We want to keep the mystery of who and what Jeremiah is alive. You know, he's been under Cadmus' control for the last 12 years and the Jeremiah that we see might not be exactly what people expected. Just to complicate the storyline for Kara and Alex," he said. "It's too good to spoil."

That sounds extremely ominous.

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On the mysterious pod man, Mon-El

The end of the second episode also saw Mon-El (Chris Wood) wake up inside the DEO and immediately try to strangle Kara. We don't know much about Mon-El, except that he landed on Earth in a Kryptonian pod and he can synthesize a building's electrical energy into power to help him self-heal. We also know that he will be the main suspect in the attack on the President of the United States (Lynda Carter) in the next episode.

"The last thing Mon-El remembers was being on an alien world and then he jumped into a pod and suddenly he wakes up on a strange world. He's all alone, he's surrounded by people with guns and he's having a reaction," Kreisberg teased. "He's reacting to the fact that he suddenly has superpowers, which he wasn't expecting."

The next episode will reveal that Mon-El and Kara have a very complex history because he's from Krypton's sister planet, Daxam. We could see Kara revert to her more jealous and judgmental ways when she learns who Mon-El truly is.

"How that story weaves about and how he and Kara come together by the end is hopefully pretty clever and interesting. We're going to explore -- in our universe -- the idea that Daxam and Krypton were sister worlds but they didn't really get along," Kreisberg said. "So there's a lot of innate hostility that Mon-El and Kara have for each other simply because of their backgrounds, which is interesting because Kara's not exactly on her best behavior. We always think Kara is so interesting when she's flawed and [when we get to watch] her learn and grow."

What did you think of "The Children of Krypton"?

Supergirl airs Mondays at 8/7c on The CW.

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