The following contains spoilers for HBO's The Last of Us Season 1, Episode 9, "Look for the Light," now available on HBO Max.

The Last of Us co-creators Neil Druckmann and Craig Mazin explain why the show needed to reveal the source of Ellie's immunity from the Cordyceps infection, with the idea dating back to when the game it adapts was first released.

Speaking with Empire, Druckmann stated the concept for Ellie's immunity was devised shortly after the original The Last of Us video game debuted in 2013, with the emotional story set to play out in an animated short that never materialized. Instead, he and Mazin saved the big reveal for the Season 1 finale "Look for the Light." “I wrote a script of the moment Ellie’s mom gave birth to her and how she was bitten exactly at that moment and had this dread of, ‘Oh my God, she’s still connected to me, I have to cut the umbilical cord!’” he said. “And then not knowing whether she cut it off in time.”

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The Last of Us Depicts Ellie's Birth

In "Look for the Light," we see the birth of Bella Ramsey's Ellie in a flashback sequence with her mother, Anna (Ashley Johnson), who crawls into an empty farmhouse mid-labor while infected hordes attack. While delivering Ellie, Anna is bitten by a clicker, sealing her eventual death but ensuring Ellie's immunity after cutting off the umbilical cord in a last-ditch effort to save her daughter. The heartbreaking scene explained why Ellie is an orphan left to be raised within the FEDRA system without any family to take care of her. Mazin suggested the tragic backstory makes Ellie a more empathetic character. “There’s just something so gorgeous about Ellie being born in violence, but also from tragedy,” he said. “That from the moment she takes her first breath, she’s losing people. That is the story of Ellie’s life."

Johnson's Anna was a Fireflies member and the best friend of Merle Dandridge's Marlene. However, the latter is left with no choice but to fatally shoot Anna after discovering her in such a tragic state after being infected, later taking baby Ellie to safety. While Johnson's role as Ellie's mother seemingly fulfilled her purpose in the series after a brief appearance, her casting was quite poetic since Johnson actually played Ellie in The Last of Us video games. She joined Dandridge and Troy Baker as voice actor alumni from the game who appeared in the live-action adaptation. Dandridge replicated her role as Merle from the game while Baker played cult follower James.

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The Last of Us Season 1 Finale Numbers

Episode 9, "Look for the Light" proved to be the peak of a historic Season 1 for The Last of Us and HBO, with the finale drawing a season-high 8.2 million viewers. With an average of 30.4 million cross-platform viewers to date, The Last of Us surpassed House of the Dragon as the most-watched HBO original series since Game of Thrones, which averaged 44.9 million viewers during its eighth and final season.

HBO has already confirmed The Last of Us Season 2 will arrive in due course, possibly beginning filming later this year according to show co-star Pedro Pascal. Furthermore, Druckmann and Mazin are already plotting Season 3 of the series, confirming their plans to cover Naughty Dog's The Last of Us Part II in the show beyond the second season.

Fans can stream all Season 1 episodes of The Last of Us via HBO Max.

Source: Empire