"Both of us were, rightly so, nervous about it," Johns says of the 12-issue series.

This November, DC's superhero universe of Superman, Lex Luthor and the Justice League will come face to face with the characters from the classic comic book series Watchmen in the upcoming mini-series Doomsday Clock — and series writer (and president of DC Films) Geoff Johns stars in a new video explaining how the story came to be.

"It's unlike any story I've ever written, and any story [artist Gary Frank has] ever drawn," Johns says of the 12-issue project in the video, before going on to remind the audience that his last comic book project — 2016's DC Universe: Rebirth special issue — set the scene for the first crossover between the DC Universe and the Watchmen universe.

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