Walking Dead Season 4 Episode 2 Live Stream Free: Watch 'Infected' Online (AMC PREVIEW VIDEO)

"The Walking Dead" Season 4 Episode 2 will air on Sunday, Oct. 20 on AMC at 9:00 p.m. ET, and will be an episode fans will not want to miss. Following last week's dramatic Season 4 premiere, today will see some important developments, and tensions will continue to build.

(PHOTO: AMC)The Walking Dead Season 4 Poster.

The Walking Dead Season 4 Episode 2 will be aired on TV on AMC, but a live stream can be found on amc.com, iTunes, Amazon, and Netflix. Alternatively the episode can be watched on demand the next day through a local cable provider.

On last week's premiere teaser, fans were told, "The group faces a new enemy; Rick and the others fight to protect their hard-won livelihood."

Then in last week's season opening it was indicated that the water might be infected and Patrick suddenly collapsed in the shower.

With water being central for the life of the survivors, anything happening to their water supply would be potentially catastrophic, and could set them a huge challenge.

Showrunner Scott Gimple told The Hollywood Reporter: "Is it safe to say this flu is impacting other survivors beyond the prison and they're turning as well? It is safe to say Patrick died of whatever that was. The walker that was at the fence that we saw was rather fresh; he's not very rotted. I would intuit that because it's a fresh zombie that the person who died recently was in the same method Patrick died."

It had been rumored that there would be a new threat to the group, other than zombies, and according to co-executive producer Denise Huth, "The relative safety that they've created at the prison begins to fall apart."

"It's someone we haven't seen before. Someone unusual; you can't stab them in the face, you can't reason with it. It's a force that would be dangerous in this world and in the world of The Walking Dead, it's terrifying," Gimple said.

The Walking Dead Season 4 Episode 2 will broadcast at 9 p.m. ET on AMC and can be watched online through live stream by clicking here.