Supergirl is gearing up for another fight with her famous cousin. During a set visit, the Girl of Steel herself Melissa Benoist teased a major fight sequence with Superman in "Elseworlds," the Arrowverse's three-show crossover.

Asked what we'll see between Supergirl and Superman in the crossover, she teased, "You can expect some really dynamo fight scenes."

During "Elseworlds," Oliver Queen and Barry Allen will swap lives. Thanks to Arkham Asylum doctor John Deegan, who was granted the power to rewrite reality by crossover villain The Monitor, Oliver is the Flash and Barry is the Green Arrow, and their respective teams are completely unaware of the switch. As such, they'll journey to Supergirl's Earth for help, where they'll meet not only her but also Lois Lane and the Man of Steel himself.

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Oliver and Barry's Freaky Friday swap won't be the only transformation in "Elseworlds." As seen in behind-the-scenes photos, Clark Kent -- or some elseworlds doppelganger of him -- will sport a black version of his iconic Superman suit. Earlier set photos showed this black-suited Superman holding Barry Allen's Flash hostage, which indicates a big superhero showdown coming up. Per Benoist's comments, Supergirl will get a few blows in before all is said and done.

This year's Arrowverse crossover event will involve the casts of Supergirl, Arrow and The Flash. The event will unfold over three nights, starting with a special episode of The Flash on Sunday December 9 at 8 pm ET/PT. Then, it continues Monday, December 10, with Arrow, and concludes on Tuesday, December 11, with Supergirl.