Different character developments occur throughout the episode, particularly with Shane Walsh (Jon Bernthal), who writer Robert Kirkman felt that viewers would no longer identify as the show's main antagonist.

Production for "TS-19" commenced at the Cobb Energy Performing Arts Centre, as opposed to the actual headquarters for the Centers of Disease Control and Prevention, which was impractical due to the high security of the area.

The episode opens with a flashback where Shane Walsh ensures that the still-unconscious Rick Grimes is secured within the hospital during the onset of the zombie apocalypse.

A drunk Shane approaches Lori Grimes about her callous attitude towards him with Rick's return and attempts to rape her, but backs off when she scratches his neck.

Jenner later shows Rick's group what he had learned from Test Subject 19, who had been his wife but volunteered to be recorded after she was bitten in hopes of discovering a cure; the infection kills the carrier but causes the brain to re-activate and re-animate the body shortly thereafter, eliminating any conscious human traits.

Jenner had been in communication with other facilities worldwide before they went silent, knowing the French had been close to a cure, but affirms that human civilization is ceasing to exist.

The group discovers that the generator's fuel reserves are near exhausted; when empty, the facility will enter a self-destruct mode by design to eradicate all the infectious diseases stored there.

Jenner seals the building, refusing to allow Rick's group to leave, but promises that the high-impulse thermobaric weapon designed to destroy the facility will mean their deaths will be quick.

[1] Actor Noah Emmerich made a guest appearance on the show, portraying the character of Edwin Jenner, one of the few remaining medical personnel dedicated to eradicating the virus.

Producers of the show were not allowed to photograph the interior of the actual buildings as part of the Centers for Disease Control and Prevention as a point of reference due to its high security.

[5] As opposed to the previous episode, where filming mostly took place outside of the Cobb Energy Performing Arts Centre, production for "TS-19" occurred inside of the building.

"When Frank was pitching the idea to me, saying he wanted to bring them to the CDC and telling me all the different things that he felt would come out of that story, the science of it all and the being trapped in the small location, I was very much picturing a lot of Day of the Dead stuff," stated comic book creator Robert Kirkman.

[5] The sequence was divided into six different cuts; the first one consisted of the rupture glass of the building, while the last frame concluded with the collapse of the Centers for Disease Control and Prevention.

[7] Kirkman asserted that the sequence added dimension to the storyline, and concluded that by the ending of the episode, the audience will no longer identify Shane as an antagonist.

[7] "Up until the sixth episode, you get the sense that Shane actually is a bad guy, that he lied to Lori and made her believe that he was dead in order to facilitate him moving in on her," said Kirkman.

[24] "TS-19" became the most-viewed cable telecast of the day, obtaining significantly higher ratings than installments of Hannah Montana and Shake It Up on Disney Channel.

In his 8.5 out of 10 rating review, Eric Goldman of IGN wrote that the episode was an exceptional showing for the series, adding that it told "a compelling, intense story within its hour" albeit averting from the comics.

[28] As Michelle Kung of The Wall Street Journal wrote, "The first season of The Walking Dead doesn’t exactly end on an optimistic note, but our heroes are left driving into the unknown after escaping certain death at the CDC.

Despite occasional stilted monologues, quick tempers and unfortunate stereotypes, the few living souls in The Walking Dead are a bigger draw than the undead.

The show has spent more time on topics like marriage, parenthood, unfaithfulness, loss, domestic violence, gender roles, small-scale politics, loyalty, kindness than it has with kill shots.

"While there was a massive fireball and a decent amount of zombie action," explained Wigler, "not to mention some concrete information regarding the outbreak, there are still several plot threads that haven't come close to resolution.

Wigler noted that Bernthal, Holden, and DeMunn delivered "brilliant character work",[18] a view that was echoed by Pierce in regards to Emmerich's performance; "He has a nervous intensity that grounded every scene he was in, which this show needs.

"[16] Similarly, Alan Sepinwall of HitFix described Emmerich's acting as "haunting", and ultimately cited the performances of Lincoln, Holden, and DeMunn as episode highlights.

[32] In a scene deleted from the television series, after Rick's group flees the CDC they return to the Atlanta nursing home they first visited in "Vatos", only to find the residents and their protectors have been killed execution-style and their supplies ransacked.