From the haunting opening credits to The Last Of Us‘ most heartbreaking deaths, the Cordyceps infection is a crucial element in the hit HBO series. The highly-acclaimed adaptation of the Naughty Dog video game of the same name, The Last of Us is an emotionally captivating take on the post-apocalyptic genre, boosted further by Pedro Pascal and Bella Ramsey’s performances as middle-aged drifter Joel and infected teenager Ellie. On their interstate journey, the duo comes across all sorts of people and, of course, those who turn into zombie-like creatures due to the Cordyceps fungal epidemic that leads humanity to a state of chaos and anarchy.
While other fictional works delving into zombies often focus on viral infections, The Last of Us is unconventional in the sense that it focuses on fungi as a potential threat to humanity. Revealed in the first two episodes and later by Joel, the Cordyceps fungal infection traces its origin to flour. It all started when the mutated fungus called Cordyceps began infecting crops and later food supplies like sugar and flour which were then blended to make ordinary shelf items like bread and cereal. With the fungi infecting hosts within a day, the show’s present-day reality came into existence.
4 The Adlers
Joel and his daughter Sarah used to live next door to the Adlers, a friendly couple who live with and take care of Sarah’s elderly mother Nana. On the day of the outbreak, Sarah can be found chatting with her neighbors. Nana is present while Mrs. Adler can be seen preparing raisin cookies in the oven. The cookies are just one of the hidden details in TLOU episode 1 as the flour used in making them carried the Cordyceps fungus. Joel and Sarah themselves narrowly missed it as they were out of pancake mix and Joel forgot to get his birthday cake.
Even though all members of the Adler family would have feasted on the cookies, the Cordyceps fungus appears to take effect in Nana’s body first as she begins attacking like an evolving clicker. Sarah finds both the Adlers to be bitten brutally by Nana who is now out of her wheelchair and ready to attack her. Nana also begins to display tendrils from her mouth through which the infected can spread the fungal infection to other humans. Given how the Adlers were bitten by Nana, it is clear that they too will turn into zombies within a matter of time.
The much-talked-about zombie kiss in The Last of Us episode 2 “Infected” killed Joel’s survivor friend Tess in a shocking manner. Escaping the Boston quarantine zone with Joel and Ellie, the trio gets pursued by two of the Infected in a museum. As Tess splits from the rest, she is revealed to have been bitten by one of them. With no way to escape her tragic fate, Tess decides to sacrifice herself. Upon reuniting with Joel and Ellie, Tess’ bite is already capable enough to turn her into an Infected.
As many more clickers corner them, Tess decides to sacrifice herself by staying back and dropping her lighter into gasoline. The ensuing explosion ends Tess’ story in The Last of Us, but the one clicker who attempts to kiss her is likely to have a specific motive. Approaching closer to Tess, the Infected’s tendrils pop out hoping to reach the similar tendrils that will soon emerge from Tess’ mouth given the Cordyceps’ presence in her body. Even though it was a bite that infected Tess, her death reveals the significance of the tendrils, a role that was otherwise fulfilled by the aerial infection-causing particles called spores in the video game.
Henry’s younger brother and a fellow survivor, Sam joins Joel and Ellie in The Last of Us episode 5 “Endure and Survive”. Despite taking precautions to avoid the Infected, the 13-year-old cannot escape from them as he is bitten on the leg by a clicker. The next day, the infection worsens, leading to a tragic conclusion for Sam and Henry’s story. Sam’s infection and eventual death prove that Ellie is quite a scientific exception as she continues to retain her human form even after being similarly bitten by an Infected before. She tries her best to save Sam, even rubbing her own blood into his wound, but to no avail.
Sam’s infection also reveals the time taken for the Codryaceps fungus to take effect in the human body. Sam gets bitten at night and then partially turns into a zombie the very next morning. If he wouldn’t have been killed at that time and lived on like this for longer than a year, his body might have fully acquired a moldy and scaly physical appearance like the terrifying clicker zombies in The Last of Us universe. While the Codryaceps fungus can take control of the host’s brain within a few hours (like in Sam’s case), it takes time for the fungus to grow externally as it does for the clickers.
Ellie’s best friend and eventual romantic interest Riley is conflicted between her friendship and her ideological loyalty to the Fireflies. Unfortunately, after a memorable night out with Ellie at an abandoned mall, Riley too suffers the same fate as Tess and Sam: she gets bitten by a runner. Even Ellie suffers a bite in the encounter, believing that she too will get infected by the fungus like her friend. Riley’s story in The Last of Us makes for one of the show’s most heartbreaking character arcs, more so as it adds to Ellie’s survivor’s guilt of having miraculously survived the bite on her hand.
Even though Riley’s death is never shown explicitly in The Last of Us, it is assumed that she dies when the infection takes hold. Going by the premise of the DLC The Last Of Us: Left Behind (on which the flashback episode featuring Riley is directly based), Riley does succumb to the infection with an unfortunate fate. But the character’s vaguely-explored ending does leave some new possibilities for the show’s later seasons. Showrunners Craig Mazin and Neil Druckmann could explore a whole new storyline where the infected Riley survives long enough to become a clicker, worsening Ellie’s fears in this process.
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