'Walking Dead' stills from Season 3 episode 11 'I Ain't a Judas': Dixon brothers battle walkers

AMC has released four additional stills from the next episode of "The Walking Dead," "I Ain't a Judas," revealing more of the group's attempt to keep the prison safe from the increased walker threat.

There's no question Merle will have to prove his worth, and it looks like he's committed to keeping the prison a walker-free zone. But is he committed enough to face down his old buddy, the Governor?

Check out even more images in our "The Walking Dead" Season 3 gallery.