Shaun of the Dead director Edgar Wright was recently asked in an interview if he would ever return to direct a TV series, and he revealed that Frank Darabont actually offered him an opportunity to direct a season 2 episode of The Walking Dead, but ufortunately it doesn't sound like he's going to do it.
Frank asked me to do a Walking Dead, actually. But I feel that there’s some subject matter that, like, even though it’d be great– and I love that show: I actually watched four of the six episodes uninterrupted in one run; it was like zombie Pringles– I think that with something like that, with some TV shows, you wanna be in on the ground floor.
Wright went on to talk about way he won't end up doing it,
Well, I really enjoyed the first season, and I wouldn’t wanna be the guy that comes in and fucks it up.
I honestly don't see how he would ruin the show! Him directing an episode would only make the series that much more awesome! Who knows... maybe he'll have a change of heart about doing it later on.