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The director Andy Muschietti was trying to figure out how to make a splash with an early scene in “The Flash.” He thought maybe a handful of babies falling from a skyscraper might do the trick.

Narrating a scene from the film, Muschietti said that the screenplay (by Christina Hodson) originally had a scene with a volcano, but that he wanted to raise the stakes. So in this sequence, Barry Allen, a.k.a. the Flash (Ezra Miller) arrives — a bit tardy — to a harrowing scene in which a building is collapsing and nine babies and a nurse are in freefall.

“I wanted to put his superpowers to a test,” Muschietti said, “and basically explaining that even if you are the fastest man alive, you can have trouble saving different people at the same time.”

The Flash’s troubles are compounded by the fact that he hasn’t had breakfast and his energy levels are dwindling, which means he slows down, and the slow-mo the audience is watching from his perspective begins to speed up. The scene is both comic and nerve-racking as the Flash uses wit (and perhaps a bag of Cheez-Its) to get him through.

Read the “Flash” review.

Read an interview with Sasha Calle, who plays Supergirl in the movie.

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