When Supergirl first made her way to the CW, fans couldn't help but wonder if she would crossover again with the other DC shows as she did with The Flash during her first season on CBS. To say fans were elated when they found out that all four shows would be involved in one this year would be an understatement, and it looks like production is already underway.

Legends of Tomorrow actress Caity Lotz shared a new picture via Twitter with Supergirl's Melissa Benoist with the caption "Seriously Super". Both are in their respective costumes, and the crossover will most likely take place in the mid to late season, so they very well could be shooting it right now.

Of course, it could be a shot from their promotional trailers for The CW, but for now the former seems more likely.

As for what to expect from the upcoming event, executive producer Marc Guggenheim told fans about the crossovers premise.

"This year, for our mega 'Arrowverse' crossover, we’re taking inspiration from a DC crossover from the late 1980s known as Invasion!, which featured an alien race called the Dominators, who’d previously vexed the Legion of Superheroes. We’re using cutting edge prosthetics and computer effects to achieve a feature film-quality look which is faithful to Invasion! artist Todd McFarlane’s interpretation of the characters.”

The Flash starts things off on October 4, closely followed by the premiere of Arrow on October 5. Supergirl premieres on October 10, while Legends of Tomorrow returns to the CW on October 13.