In a new trailer for The Flash that screened Saturday evening at Comic-Con, Barry (Grant Gustin) narrates, "Some things happen by chance, and some things happen because we make them happen."

There could be no better theme for Season 3 of The Flash, which — as has already been excitedly reported — will deal with Flashpoint aka a new world, thanks to the events of the Season 2 finale. If you need a reminder, Barry chose to go back in time, save his parents and live in a world where they survive.

Needless to say, his choice is going to have some major consequences throughout the universe, many of which were teased during the panel Saturday.

Below, check out 10 things we learned about the new seasons of both The Flash and Supergirl (which had its Comic-Con panel right beforehand). To get it out of the way early: Yes, more crossovers — this time, among all the properties — are planned.

1. When The Flash picks up, it's been three months after the events of the finale. "First Barry doesn't realize how much has changed," Gustin teased. "The whole reason he did this is his parents would be alive. When we first see him, he's unaware of what changes are out there.”

2. "We’re doing two Big Bads [this year]," executive producer Todd Helbing explained. "One is a speedster. The other is Dr. Alchemy."

3. As seen in the new footage, Cisco has undergone quite a transformation in the new timeline. Cisco is "an ostentatious billionaire," Carlos Verdes teased about his character. His speciality? "Making money. He's always flexing how much money he has and how rich he is."

4. Tom Felton will be joining The Flash as Julian Dorn. Felton was fairly tight-lipped about where his character's loyalties are, but when asked if Barry and Co. should see him as a threat, he cackled, "I think any guy I play you should see as a threat ... There's definitely some friction between Grant and Julian." Well played, Draco Malfoy.

5. On the Supergirl front, the show will be moving from CBS to The CW when it returns — making even more crossovers between the various metahuman shows likely. "We're so grateful to CBS [for] launching this show, but we were all thrilled to learn about this because we do so much with The CW," Supergirl executive producer Sarah Schechter said. "If you say metahuman, they know what you're talking about. We're happy to have everyone in the same place, literally and channel-wise."

6. What's Alex up to in Season 2? "What's really cool about this season is we've established so much about who Alex is in the DEO and her relationships with John and Kara," Chyler Leigh shared. "But we didn't really get to see much of her outside those elements. This season is an opportunity to see who she is and what she wants outside of that … Where does Alex live? I have no idea."

7. Quick recap: Jimmy and Kara kissed at the end of Season 1 of Supergirl. Is that ship going to sail come Season 2? "We ended up in a liplock," Mehcad Brooks teased. "It's weird because I read [episode] 201 and it starts with our wedding [laughs]. It's a workplace relationship; it's a new relationship it's going to have ups and down. We're both figuring out who we are and that may get in the way. We'll see!"

8. Tyler Hoechlin is joining Supergirl as Superman. How does it feel to step into the iconic suit — which Hoechlin noted he has not yet tried on? "Incredibly surreal. I know this character means so much to so many people. There's a responsibly to the character. I take it on with great pride. I'm excited to see what we do with that character in the context of this great world you've created."

9. Wonder Woman Lynda Carter is joining the show as the President. "I think we should expect that a female president is going to lead well," Schechter said with a knowing wink. "We're with her."

10. Between Melissa Benoist's stint on Glee and Jeremy Jordan's on Smash, it's no wonder many fans are pulling for a musical episode of Supergirl at some point. "It would be silly not to recognize all the talent," Schechter noted. "We've thought about it." The cast then pointed out that between takes on set, it already is pretty much a 24/7 musical.

Psst…can we get some footage of that? Thanks in advance.

Supergirl will premiere Oct. 10; The Flash will return Oct. 4

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