When Robert Kirkman, the creator of The Walking Dead franchise, first developed the idea of a zombie apocalypse, he gave little thought to how and why the zombie virus was created. While writing The Walking Dead comic book series, which debuted in 2003 and ended in 2019 after 193 issues, Kirkman deliberately avoided revealing the origin of the zombie virus, focusing instead on character development and the moral dilemmas that arise from the zombie apocalypse.

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