Killer Within

"Killer Within" is the fourth episode of the third seasonof AMC's The Walking Dead. It is the twenty-third episode of the series overall. It premiered on November 4, 2012. It was written by Sang Kyu Kimand directed by Guy Ferland.

Plot
The group is severed and lives are put in jeopardy. In Woodbury, Merle has a request for the Governor.

Co-Stars
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 * Markice Moore as Andrew
 * Vincent Ward as Oscar

Uncredited

 * Adelaide and Eliza Cornwell as Judith Grimes
 * Randy Woods as Mr. Jacobson
 * Keith Andrew Gostel as "Woodbury Resident"
 * Deanna Dixon as "Woodbury Resident"
 * Greg Tresan as Richard Foster
 * Carol Lane Tresan as Mrs. Foster
 * Devon Tresan as "Foster's Daughter"
 * Bill Vella as "Woodbury Resident"
 * Nikki Barnett as "Woodbury Resident"
 * Elberta McKnight as "Woodbury Resident"
 * Aaron Parr as "Woodbury Resident"
 * Elizabeth Davidovich and Johnny Cooper as Stunt Walkers
 * Lauren Henneberg, Ryan Nesset, Andrew S. McMillan, Amanda Adams, Alyssa V. Mullan, Dan Riker, Kasey Williamson, John Jaret, Jonna Capehart, Ashe Johnson and Gary LaVard as Walkers
 * }
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Deaths

 * Theodore Douglas
 * Andrew
 * Lori Grimes
 * 1 deer

Trivia

 * First appearance of Judith Grimes.
 * First appearance of Mr. Jacobson.
 * Last appearance of Lori Grimes. (Alive)
 * Last appearance of T-Dog.
 * Last appearance of Andrew.
 * Last appearance of the Greene Family Farm.
 * The title of the episode, "Killer Within", refers to Andrew being the "killer" inside the prison. He released the walkers into the prison, which killed T-Dog and prevented Lori from having a stable C-Section.
 * It may also refer to Lori's baby, as it is the main cause of her death, albeit indirectly.
 * This was one of the most emotional and difficult episodes to shoot for the cast and crew.
 * This episode was referenced in an episode of The Big Bang Theory by Sheldon Cooper. Sheldon asked Leonard Hofstadter if he would like to catch up on The Walking Dead, Sheldon then asked if Leonard had seen "the one where Lori dies", thus spoiling the ending.
 * This is the only episode in Season 3 where all of the Main Cast appear in physical form.
 * This is mainly due to the fact The Governor was only introduced in the previous episode and Lori Grimes dies in this episode.
 * In this episode, Carol was originally supposed to die, but the producers decided against it.[1]
 * When shooting the scene of Rick discovering the demise of Lori, Andrew Lincoln asked Sarah not to be around the set while he is shooting that particular scene. "Andy asked me not to be on set. But I couldn't leave, so I was at base camp with the trailers. I could hear him screaming and crying. I was sitting there with IronE Singleton kind of going, "Oh my God. This is horrible." And then one by one as the scene ended they came back to the trailers to change and go home, and I put my arms around Andy. When he goes down the rabbit hole he goes all the way down. I put my arms around him and I was like, "Look at me. I'm right here. I'm alive! Andy and Sarah are just fine. Rick and Lori are over, but Andy and Sarah are just fine." Sarah said.
 * In this episode, there were 24 confirmed walker kills and three living humans. Rick Grimes had the most kills with 6 walkers.

Comic Parallels

 * Lori giving birth to Judith is adapted from Issue 39.
 * Andrew revealing himself to be responsible for the prison chaos after attacking Rick in the generator room is adapted from a similar scene in Issue 16, where Thomas reveals himself to be the prison killer after attacking Andrea in the laundry room.