The CW’s ‘Arrowverse’ has grown over the last few years from a guy in a green hood intimidating rich people into whole universe of comic-book characters from the Flash to Supergirl. It culminated last fall in a massive crossover that featured nearly 20 superheroes fighting evil Nazi versions of themselves from an alternate universe. We wondered at the time how the 2018 crossover could possibly go bigger. As the event nears, the picture is starting to come into focus. Instead of going bigger, the Arrowverse is focusing and bringing in some big guns.

Season 2 of Supergirl kicked off with a two-parter appearance by the man of steel himself, Superman, played by Tyler Hoechlin. Supes is returning for this crossover, and he’s bringing backup in the form of Lois Lane. Lois Lane hasn’t been cast just yet, but Hoechlin will be reprising his role. This is on top of the debut of Batwoman, secret identity Kate Kate, who will be played by actress Ruby Rose, possibly as prep for her own standalone series.

“We couldn’t be more excited to introduce Lois Lane to the Arrowverse,” Supergirl executive producers Jessica Queller and Robert Rovner said in a prepared statement. “This dogged, determined and brave reporter will make for a strong partner to Superman and amazing addition to our universe of DC characters.”

To help focus the group down, the Legends of Tomorrow cast is sitting this one out. They’ll presumably have their own thing going on, and John Constantine is joining the crew from his cancelled NBC show as a series regular, so they’ll have plenty of stuff to do without taking a break to go to Gotham city. Which, with to focus on Batwoman, is presumably where things are going this year.

One of the big questions I haven’t seen answered just yet is which ‘Earth’ the show will take place on. In the Arrowverse, Flash and Arrow live on Earth One, while Supergirl and her cousin live on Earth Thirty-Eight. Last year, Supergirl and the crew went to Earth-X. Will Barry and Ollie go to Earth Thirty-Eight, or is the House of El going to drag Lois over to Earth One? Supergirl has already dropped hints a couple times that Batman might exist on Earth Thirty-Eight, so it would make sense that that’s where Batwoman exists, and it would make for some easy casual crossovers between two woman-centric shows, so I’m kind of hoping the crossover will take place there. It’s worth noting that the CW’s Black Lightning exists in its own, third universe, and isn’t involved in this crossover as of this writing.

Either way, this all sounds like a blast. With the Legends doing their own thing, we’ll be able to spend more time with Batwoman, Superman, and Lois Lane as they meet the characters we already know and (sometimes) love.

The crossover is a three-night event this year, kicking off on Sunday, December 9.