Why did the Arrowverse reveal “Crisis on Infinite Earths” as the title of its Fall 2019 crossover event the instant that 2018’s “Elseworlds” came to a close?

Simply said, because it is that big of a deal. In every way.

“It will be the biggest and most complicated [crossover yet],” CW president Mark Pedowitz avowed at the Television Critics Association winter press tour on Thursday afternoon.

At the very end of “Elseworlds,” Batwoman (played by Ruby Rose) called Oliver Queen from Gotham City, to express her concern about new Arkham Asylum inmate Dr. John Deegan — because, she noted, the man who for a hot second imagined himself a god had “made a friend” in Roger Hayden, who in DC Comics lore is also known as Psycho-Pirate.

“Everything is as it should be, the stage is set…,” Hayden, donning Psycho-Pirate’s golden mask, gloated to Deegan. “Worlds will live. Worlds will die. The universe will never be the same.”

The screen then cut to a title card that said “COMING FALL 2019… CRISIS ON INFINITE EARTHS,” as in the name of the super-famous DC Comics storyline in which the Anti-Monitor — The Monitor’s evil counterpart, who counts Psycho-Pirate among his accomplices — is unleashed on the multiverse and begins to destroy the various Earths that it comprises.

Along the way, top-shelf heroes die. Will the TV crossover take similarly big swings?

“That is the intent, to take some big swings,” Pedowitz affirmed for TVLine. “Can’t tell you if it’ll follow the comic book version, but it’ll take some big swings.”

As for Legends of Tomorrow possibly returning to the crossover mix after sitting out “Elseworlds,” Pedowitz said he didn’t know the plan yet, but “I hope so.”

“We’re talking about a number of different ways to go,” he added. “It is ‘Crisis on Infinite Earths,’ and if you know the history, things collapse.” (With reporting by Vlada Gelman)

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