Robert Kirkman explains how aliens almost invaded The Walking Dead 

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creator Robert Kirkman was throwing them for a loop when he made a “ridiculous” addition to the 75th issue of his popular comic book series.

, Kirkman went back to the early days of his series, which began 14 years ago, when it was just gaining steam. “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,’” he recalled. “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.’”

Of course, Kirkman did eventually get to lucky No. 75 with his series more popular than ever, but that particular issue emerged as something of an anticipated inside joke among fans. “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,” he said. “Like, ‘Oh, 75, that’s when the aliens come in, right?’” Kirkman knew he’d have to do something — a “gag” to make all his joking responses pay off.

He ended up making a slight change that had panicked fans writing, “You’ve ruined the comic!” As he remembers it, “People were freaking out for a while!” But what did Kirkman do, exactly? Watch the 

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