A new character from The Last of Us episode 4 is essential to the show, and the showrunners explain why. While The Last of Us focuses on the stories of Ellie (Bella Ramsey) and Joel (Pedro Pascal) as they travel across the country searching for the Fireflies and Joel's brother, episode 4 sees them trapped in Kansas City as they contemplate their next move. All the while, Kathleen (Melanie Lynskey) is getting ready to hunt them both.

As The Last of Us continues its remarkable viewer growth and staying power, showrunners Craig Mazin and Neil Druckmann ed The Last of Us Podcast to explain why they introduced Kathleen.

Since Kathleen is an original character who does not appear in the game The Last of Us, her introduction in the HBO series is a surprising twist in the story. With new enemies around every corner, Ellie and Joel are in more danger than ever, and the creators were ready to explain why they added these new villains. Check out their quote below, via Collider:

"The show affords us the ability to leave Joel and Ellie and flesh out other characters, in different ways. The best thing you can do in The Last of Us is flesh out your antagonists. They don’t see themselves as the villains, they have their own motivations, we are just at odds with each others, our goals just overlap. To leave Joel and Ellie and put a face on the resistance that took over the quarantine zone from F.E.D.R.A. made them more interesting, to show the duo and this group careening towards each other makes you cringe because you know what’s coming.

Humanity will probably not descend into a Mad Max-style culture in a post-apocalyptic world where 80 people just love killing. It’s not what happens. What happens instead is we’re 80 people who love each other as family, friends and neighbors and that means we must protect ourselves at any cost, and anyone who gets in our way must be taken out. Joel was once one of those people. That’s how he knows the guy asking for help isn’t hurt, and they’re being conned. It was important for us to put a face on these people, so we have this character in Kathleen who we understand is suffering when we meet her. Even though she has the gun in her hand, she is suffering. We have this revolutionary who quietly becomes a terror and does horrible things in service of this, but is still someone we empathize with."

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Other Deviations HBO Made From The Last Of Us

A Kansas City soldier leading the team in The Last Of Us episode 4

Kathleen isn't the only difference between the HBO show and the games. The Last of Us makes big changes to the route that Ellie and Joel take along their way to Tommy. Instead of meeting Henry (Lamar Johnson) and Sam (Keivonn Woodard) in Pittsburgh, the two find themselves in Kansas City. While it may not make a huge change from the story, it is somewhat confusing that the survivors are so far off course in Kansas City, despite heading from Boston to Wyoming.

The changes aren't only superficial. The survivors also have to face off against a very different overarching threat, as the tendrils emerging from the mouths of the infected aren't actually in the game. It is a major zombie element changed for HBO's The Last of Us, as the games instead use spores. Characters have to wear gas masks everywhere they go to avoid breathing in the infectious spores, which likely contributed to the zombie changes in the show.

The show also makes timeline changes with the infection's onset, starting in 2003 rather than in 2013. This makes the story take place in modern times, which helps to provide an interesting juxtaposition compared to the real world. The story itself is also more condensed due to Joel's need to find Tommy, which makes the encounters with Kathleen even more harrowing in The Last of Us. With an earlier episode drop on HBO Max on February 10, episode 5 will likely uncover more of Kathleen's motive.

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Source: The Last of Us Podcast (via Collider)