The Flash And Supergirl Showrunner Doesn't Know If The Two Series Could Legally Crossover

For the second time this week, an executive producer for The Flash and Supergirl has shot down rumors of a crossover between those two shows.

This time, Andrew Kreisberg told us and a group of other reporters at a recent set visit that he's not even sure if such a crossover is a legal possibility.

"There's always those late nights, delirious, semi-high on pizza where you're like, 'You know what would be really cool? If …,' "Kreisberg said. "But right now there is no legitimate actual plan to bring [The Flash's] Cisco [Carlos Valdes] onto Supergirl or to bring [Supergirl's] Winn [Jeremy Jordan] onto Legends [of Tomorrow]. First of all, we don't even know if we could, legally. And quite frankly, just making the Arrow-verse, which is what we call Legends, Flash and Arrow work and then making Supergirl work, it's enough of a challenge without having to add a fourth player."

Fans will just have to enjoy their superhero chocolate and peanut butter separately for the time being.

Supergirl airs Mondays at 8 p.m. ET on CBS.

The Flash airs Tuesdays at 8 p.m. ET on the CW.