Flash Meets Flash! Grant Gustin and a Gobsmacked Melissa Benoist React to Movie Hero's Cameo in 'Crisis'

Even Supergirl’s super vision didn’t see this one coming.

We’re of course talking about Tuesday’s surprise “Crisis on Infinite Earths” cameo. Midway through the Arrow portion of the annual CW crossover, Ezra Miller’s big-screen version of The Flash appeared opposite Grant Gustin’s Barry Allen. The sequence in question took place at STAR Labs, as Barry struggled with his re-entry into the Speed Force. After expressing puzzlement at the whole situation unfolding before them, movie Flash and TV Flash paused for a moment to admire each other’s suits. (Is breathability more important than being safe?)

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After the scene aired on the West Coast, Gustin reacted to Miller’s top-secret appearance.

“How about that?” he wrote on Instagram. “Ezra is one of a kind. So glad we could make this happen and keep it a secret until today. Thank you to @dccomics.”

Shortly thereafter, Supergirl‘s Melissa Benoist slid into Gustin’s comments with a reaction of her own. “YOU KEPT THIS SECRET SO WELL,” she said. “NONE of us knew!!!! Or did they know?! Was I the only one that didn’t know?!”

Later that night, Arrow EP Marc Guggenheim acknowledged the cameo on Twitter and gave credit to DC Comics’ Chief Creative Officer Jim Lee, who was “instrumental in making this moment happen.”

Scroll down to see additional photos from the epic crossover.

Launch Gallery: 'Crisis on Infinite Earths' Burning Qs Answered!

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