Chris McKay, the animation supervisor on Lego Movie, was initially set to direct that project's sequel. However, the movie is being pushed back and McKay is now helming the Lego Batman movie, which is being written by author-screenwriter Seth Grahame-Smith.

Warners is eyeing a 2017 release for the spinoff, possibly even on the original date for Lego Movie 2. The next Lego movie to be released is Ninjago, due to open Sept. 23, 2016. The Lego Movie sequel will now presumably be released after 2017.

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Will Arnett will reprise the voice of the Caped Crusader. Roy Lee, Dan Lin, Phil Lord and Christopher Miller, the custodians of the Lego screen brand, are producing.

Batman was one of the highlights of The Lego Movie, stealing every scene he was in. With Arnett taking Christian Bale's gravely voice to an extreme degree, the character was arrogant, dark, sarcastic and just too-cool-for-this-adventure.

Lego Batman already heads a very popular franchise. There have been at least three video games as well as a straight-to-video Lego Batman: The Movie — DC Super Heroes Unite, where Troy Baker provided the voice for the Dark Knight.

Warners had no comment.

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