‘The Walking Dead’ Season 4 Spoilers: Andrew Lincoln Reveals New Cast And New Challenges [VIDEO]

"The Walking Dead" returns Sunday for Season 4, and despite how long Rick's crew has been surviving in a post-apocalyptic world, their lives are not getting any easier. But even though "The Walking Dead" won't be getting any better for the cast, Season 4 will be better for the fans! Based on promo videos for the upcoming season, the series is about to embark on its best season yet. We meet back up with the survivors in the prison, and along with Rick's groups and the Woodbury survivors, the prison is bustling. Even though life is a bit more settled the walkers are still a constant threat and more terrifying than the presence of zombies is their continuing growth.

Another concerning fact about the walkers, is that is Season 4 they are more organized and seem even more aware. Leaving fans to wonder, is someone organizing the walkers? Or are they learning how to organize themselves? The growing number of walkers are shown attacking the weak points of the prison, they also breach the structure and attack a cell block. The trailer leaves questions unanswered, like just how exactly the walkers infiltrate the cell block? Despite, all the unanswered questions, the Season 4 promo video does reveal that someone has been feeding them and that Rick thinks someone on the inside allowed the walkers into the cell block leaving 12 dead.

But the growing walkers is not the only threat that the survivors are facing. Andrew Lincoln, who portrays Rick, revealed that due to the growing number of survivors and the dwindling amount of supplies, life in the prison is anything but idyllic. "There's around about 50 new characters, which puts obviously an enormous amount of pressure on the group with the practical necessities of food and water," Andrew tells Entertainment Weekly. "It is a third-world environment that we're existing in now."

And as if the group needs any more problems, the growing community of survivors just can't play nice. The group's tension is palpable, and adding to the drama is the fact that Rick is no longer the sole leader. The prison has installed a governing body of a council to oversee life, however, it may have just been easier when Rick was the judge, jury and executioner. Lincoln gave fans a more in-depth look at the character relations in Season 4, "We were a band of maybe 10 characters at the end of last season, so the character relationships and the group dynamics have changed radically," Andrew explains. "There are always going to be tensions within the group ... and you find us in a place where people are trying to wrestle with those problems as well as, obviously, the pressure of the walkers and survival."

Season 4 of "The Walking Dead" returns to AMC on Sunday, October 13 at 9/8c. Check out a promo video for Seasn 4 below: