"But I was listening to him before we went on stage, Kirkman was up there talking about it along with [TWD chief content officer Scott Gimple], and talking about where and how this show exists within the confines of what the comic book was. And they're quite sure that there's plenty of story, not only based on what was written that Robert did, but beyond that, because we have deviated enough."
One key deviation was always the presence of Norman Reedus, a freshman season veteran whose Daryl was created for the show. Reedus has since become first billed following the Season 9 departure of Rick Grimes star Andrew Lincoln.
"The biggest difference was always Daryl, who was not part of the comics, and look at him now," Morgan said, noting the television series will continue "as long as we have people like [showrunner Angela Kang] running the show, and they've got an idea where these stories are going."
"But you hate that the comic book ended," Morgan added, "just as a fan of that kind of genre."
"I was on set that day and folks were just like, 'What does this mean?!'" said Michonne star Danai Gurira.
"He ended it like real life ends," Reedus added.
"I remember that character Axel on our show, [Carol] was talking to him, and he gets just shot and dies. It was like one of the best killings on our show, because it happened in real time. I think if Kirkman had a long, drawn out ending, we wouldn't have liked it."
When appearing at TWD's Hall H panel, Kirkman said the book was Rick and Carl Grimes' story and it was one that had reached its "natural conclusion."
But the television series — which killed off Chandler Riggs' Carl in Season 8 and wrote off Lincoln's Rick in Season 9 — is "about the world, and we've proven that with the last season," Kirkman said.
"Anyone that's concerned that the fact that this comic book wrapped up means that Season 10 is going to somehow spontaneously end on episode 4 as a surprise, that is not going to happen," Kirkman said.
"There's a lot more story to tell, and I'm very excited to be working with Scott and Angela to figure out if there are any other threads in the comic that we didn't quite get to, to bring the world past that point. Because I think there is some story to tell when you're talking about the world of The Walking Dead. So I'm very excited about that, so no worries there."
The Walking Dead Season 10 premieres Sunday, October 6 on AMC.