When 'The Walking Dead' first started, whether you were following the comic books or the television series on AMC, you would have seen it kick off with lead character Rick Grimes (played by Andrew Lincoln on the show) waking from his coma. Upon his revival, he would realise that he was in the midst of a zombie apocalypse - something that he would find out had been going on for some time. Since that point, the narrative has been solely focused on each of the characters and their individual stories, as well as their fight for survival.

Robert Kirkman is the man responsible for creating 'The Walking Dead'Robert Kirkman is the man responsible for creating 'The Walking Dead'

One piece of plot that we're still yet to find out however is exactly why the dead started to rise up and feast on human flesh. It's something that's usually explained in a series or a film of this type, and so creator Robert Kirkman has certainly broke the mould. The writer isn't in any rush to give the explanation behind the outbreak, either.

Asked about the origins of the zombie outbreak by a fan during a Tumblr Q&A, Kirkman responded: "I know… but it’s a crazy sci-fi thing that would make the story all that much weirder. Maybe years after it’s all over I’ll just casually mention it in an interview. That seems like a very J.K. Rowling thing to do. It couldn’t be less important to the story and the lives of these characters. It would be completely out of place in the story. Honestly if a scientist from Washington came to the character and told them what happened the characters would just shrug and say “Oh… okay…” it wouldn’t change their lives at all… and… I’ve said too much."

With Kirkman downplaying the reasoning behind the outbreak, fans have to respect his decision not to reveal it. At this point, it would probably feel like more of a novelty thing to win viewers back any way, rather than being done for any good reason and for the sake of the story.

Still, as the writer teased, he may just drop the topic into conversation one day when 'The Walking Dead' comes to an end. Whenever that may be however is anybody's guess...

More: Robert Kirkman Defends Decision To Kill Off Carl In 'The Walking Dead'

'The Walking Dead' continues Sundays in the US on AMC and Mondays in the UK on FOX and NOW TV.