Editor's Note: The following contains spoilers from Episode 7 of The Last of Us.When Naughty Dog began developing the video game that would eventually become The Last of Us in 2009, they had a clear aim of delivering a mature and gripping narrative experience. By the time the game was released in 2013, it was incredibly clear that the objective was accomplished. The story of Joel (Troy Baker) and Ellie's (Ashley Johnson) American exodus took the world by storm, but that doesn't mean that every aspect of the two protagonists was explained outright.

Specifically, while players encountered the tragic backstory of Joel's character in the game's opening moments, much of Ellie's life before meeting Joel was left shrouded in mystery. Naughty Dog set out to address this, and released a downloadable chapter in February 2014 known as "Left Behind". This DLC took place during Joel's incapacitation after a fight at the University of Eastern Colorado, but heavily featured flashbacks into Ellie's past in the Boston Quarantine Zone and her relationship with Riley Abel (Yaani King).

The DLC was a huge unveiling of many of the mysteries surrounding Ellie's character. However, the release after the game's launch also came a bit late, as some players and fans likely felt a bit weird stepping back into the middle of the game's story after having already completed it. Fast-forward to 2023, and the smash-hit game has produced worldwide acclaim once again thanks to its adaptation on HBO Max. The series' seventh overall episode is dedicated to the Left Behind chapter of the game and provides even more narrative punch than it could ever have as a DLC to the original game.

Why Left Behind is Vastly Improved in HBO's The Last of Us

Ellie (Bella Ramsey) telling Riley (Storm Reid) pins in The Last of Us
Image via HBO

One of the largest reasons why "The Last of Us" has been as successful as it has been on TV is due to the benefit of retrospect. For Neil Druckmann, who co-wrote the original game and co-writes, directs, and produces the HBO adaptation, having ten years to look back on the game has been a huge help for the creative process. In several post-episode behind-the-scenes interviews, Druckmann remarked that analyzing what worked for the game's story and what fell short has been a boon for charting out the direction of the show along with Craig Mazin. Anybody who has played the first game and has watched the show can clearly see the discrepancies between the two, and the care that Druckmann and Mazin take to keep the core of the game's narrative and world intact is present in every single episode.

Though sticking to the source material of such a massively-popular game is smart in general for any televised or film adaptation, there are times when creators can make changes or expand on the story without veering off-course completely. Look no further than the show's third episode "Long, Long Time" to see how well Druckmann and Mazin can take something as small as a written note from the game and spin it into an unforgettable hour and fifteen minutes of storytelling.

In many ways, "Left Behind" always felt like a chapter in the game that should have been a part of the main story, but development simply didn't pan out that way. However, as they say, hindsight is 20/20, and it's clear that Druckmann and Mazin made a point of including the chapter in the first season of the show given how crucial it was to Ellie's (Bella Ramsey) continued development. To this point in the season, viewers have certainly gotten to know Joel (Pedro Pascal) and Ellie, but the grittier details about Ellie discovering her immunity to Cordyceps Brain Infection and the people she lost before she met Joel needed to come into focus. Not including these details in the original game until months afterward was likely a difficult choice to make for Druckmann and Naughty Dog, but ten years of reflection allowed for that oversight to be taken care of in the TV adaptation.

"Left Behind" Adds Emotional and Thematic Value to Ellie and Joel's Journey

Ellie (Bella Ramsey) and Riley (Storm Reid) in The Last of Us exploring the mall
Image via HBO

Thanks to the creative change in the HBO series, Ellie's entire backstory begins to show the bigger picture of who she is. The show's story doesn't go on a tangent thanks to Episode 7's bookends of Ellie looking after Joel as he suffers from a stab wound, and viewers are still able to meet Riley (Storm Reid) and experience the young love she and Ellie shared before it was tragically snatched away from them due to the intervention of the infected. In so doing, watchers are given an understanding of Ellie's Survivor's Guilt and losing the one person she cared about most. To longtime series fans and newcomers alike, Left Behind is a pivotal moment in showing why Ellie has to pursue the possibility that her body carries a potential cure for cordyceps infection.

Sure, fans of the game certainly came to this realization, but many did so after already experiencing the end of the first game and all that it entails for the future of the post-pandemic world. Those few months between The Last Of Us' release on Playstation 3 and the Left Behind chapter's DLC debut was more than enough time to process and square away the drama and heartache that occurred in the game's story. But by including the plot of Left Behind squarely into the main narrative of the show, nobody is left out of the thematic value that it provides. Now, when watchers experience the end of the first game's narrative, it's hard not to imagine that they'll be doing so with much more feeling thanks to Ellie and Riley's backstory being explored during, not after, the primary sequence of events. The added exposition gives even more emotional weight to what lies ahead for Joel and Ellie as they seek out the Fireflies in hopes of healing a blighted world.

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