The Walking Dead is one of the strongest brands in pop culture. Between The Walking Dead and Fear The Walking Dead, the shows have managed to dominate TV, but the comic book is still going very strong as well. Robert Kirkman is now 14 years and 172 issues in, but there was a point where he thought he would run out of ideas. His solution? Bringing in aliens.

As hard as it may be to believe, there was a time when Robert Kirkman thought that he was going to run out of ideas for The Walking Dead. How many times can you make the whole zombie thing work? Fans began writing him suspecting that the idea doesn't "have any legs." So, he started joking with fans that, when the book hits issue #75, they're going to bring in aliens and the book will "jump the shark." Here's what he had to say about it.

"Very early on in the series I started getting letters where people would say, 'You say you're going to do this book for a really long time, but this idea doesn't seem to have any legs.' My response as a joke was, 'Oh, we're going to this until issue 75, and then I'm going to run out of ideas, and then I'm going to do an alien invasion and just kind of completely ruin the book. That's when we'll jump the shark and it'll be terrible and everybody will hate it.'"

Believe it or not, Robert Kirkman actually lived up to that promise. Issue #75 of The Walking Dead does feature aliens, but only as a joke. He wrote an alternate ending to the issue that depicted aliens actually coming to Earth and invading. At that point, the Governor was already dead, but they brought him back as a one-eyed cyborg, and they decided to put Rick in a superhero costume. It was all in the name of fun, but some fans didn't see it that way.

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""When we got to issue 75, I knew that I'd publicly joked about that and it was kind of a thing that the fanbase knew about. Like, 'Oh, 75, that's when the aliens come in, right?'"

In the "letter hacks" section in the middle of the issue, Robert Kirkman let fans know that it was all a joke, but since not everyone read that section of the comic, many fans said he "ruined" The Walking Dead. Even in a world where zombies have taken over the planet, aliens invading is pretty tough to swallow. What are the odds that both of those things would happen at the same time?

Kirkman recounted this story for Entertainment Weekly just ahead of The Walking Dead season 8 premiere. So is there any chance we'll ever see this happen on The Walking Dead or Fear The Walking Dead? Absolutely not, especially since the show has far surpassed the point where that happened in the comics. But one can dream.