BEVERLY HILLS - It's hard to complain about anything when the entire world appears to be suffering through a zombie apocalypse, but any viewer of "The Walking Dead" has to feel for series hero Rick Grimes (Andrew Lincoln).  The former law enforcement officer awoke from a coma in season one to find Atlanta overrun by zombies.  By season three his wife Lori (Sarah Wayne Callies) has passed away giving birth to a child which likely isn't his own. Add on the constant stress of zombie hordes and an ethically challenged "Governor" and it's not surprising Rick's gone a little off the deep end this season.

Lincoln spoke to HitFix before "The Walking Dead's" PaleyFest Q&A Friday night in Beverly Hills.  The 39-year-old actor warns viewers that Rick's trauma is not something that's going to magically disappear overnight.

"I think he's had a complete breakdown and I think he's suffering from post-traumatic sleep disorder, grief," Lincoln says. "And all of these things are playing on him and he's just -- the scene with Hershel. Hershel realizes as a doctor as a man of medicine that [Rick] needs to process. That's the thing about the show. The show moves so quickly that people don't have time catch up with the trauma of what's happened to them. So, I think for the first time the audience is living the trauma with Rick and I think it takes time. Anybody who has lost anybody, I'm sure you know. It's not an instant overnight fix. And certainly in this environment, this hell it's even harder. And of course they are all have the added complication of [The Governor] trying to kill them."


And as for the threat that any "Dead" character can fall victim to any number of dangerous forces in this alternate universe?  Well, every job has it's drawbacks. Recently, Rick had to relive Lori's death once more with his seemingly departed co-star.

"It's a tough damn show and the only downside about it is that you lose such great friends and such great actors," Lincoln admits. "And interestingly, I witness her death, but then we had to do it again. In sort of my own mind, so it was really hard and painful and exactly what you see on the screen. No one really wants to leave the show."

For our complete interview with Lincoln, watch the video embedded at the top of this article.

For 20 things we learned from "The Walking Dead" panel click here.

A new episode of "The Walking Dead" airs Sunday night.