We’re heading into week 5 of Arrow and The Flash, which means there’s only a little over a month until the DC TV Invasion! crossover where Supergirl, The Flash, Green Arrow and the Legends will face the biggest threat the Arrowverse has ever seen. It will take all of them to defeat The Dominators, a tech-savvy alien race who will attack Earth to eliminate metahumans. On Saturday at EW PopFest (via ComicBook), DC TV stars Stephen Amell, Melissa Benoist and Grant Gustin spoke on the Invasion! crossover event.

"We had our individual scenes, but then we had scenes where there were like 20 superheroes there in this big airplane hangar. And it looked like and felt like — and I think the fans will feel like — this is a big 3-4 hour movie that we are putting on,” said Amell.

If you thought last year’s crossover was epic, just imagine 20 superheroes in one scene. The scope of the event is certainly ambitious, but Gustin thinks the risk of putting it together will pay off.

"It's just a lot bigger," Gustin said. "Last year was Flash and Arrow and now... We have 17 characters in multiple scenes and almost everyone interacts with every other character, at a certain points. So, it's huge! Huge,” Gustin said.

This will be the first time Supergirl has stepped foot in the Arrowverse. Greg Berlanti calls Supergirl's home Earth-CBS. Last season, we saw The Flash end up in National City. This year, it’s the other way around. We got a chance to see Supergirl and Green Arrow interact in Superhero Fight Club 2.0, but the crossover event will make her induction official.

Executive Producer Greg Berlanti also talked about the logistics. The crossover will begin in Central City, but Supergirl will be brought in before the story officially picks up with The Flash on Tuesday.

“It starts a little at the tail-end of Supergirl , because she's in a whole other universe, on a whole other planet, so having to go get her. And then it really begins on the night of The Flash . It's three parts and called 'Invasion.' The complex they talked about shooting in: We found an exterior shot that looks a lot like the Hall of Justice, so we like that,” Berlanti explained.

Benoist, Gustin and Amell also argued over which hero would win if they had to fight each other at PopFest. Considering she has heat vision and flies, Benoist is confident Supergirl would win. However, Amell’s character is certainly the most calculating and experienced. Berlanti concluded we’ll have a better idea of who would come out on top after the crossover event.

While it hasn’t been confirmed, based on statements from the cast and producers, the crossover schedule is as follows.

Supergirl Season 2 episode 7, Nov. 28

The Flash Season 3 episode 8, Nov. 29

Arrow Season 5 episode 8, Nov. 30

Legends Season 2 episode 7, Dec. 1

Supergirl Season 2 episode 8, Dec. 5