Spoilers for The Last Of Us season finale are ahead.
While not every mystery of The Last Of Us has been solved, the season finale of the series has given us some answers, while also leaving us with even more questions. But fans finally learned the reason why Ellie is immune to the virus that has been destroying the Last of Us universe, thanks to her harrowing birth.
In the finale, there is a flashback that showed Ellie’s mom Anna, played by Ellie’s video game voice actress Ashley Johnson, giving birth to her all those years ago. The grueling scene shows that Anna was able to have her daughter just moments before an Infected lunges at them both. Anna becomes infected while the infant is still attached to her via umbilical chord, though she lies and insists to Fireflies leader Marlene that she must be protected. Marlene is then forced to kill the newly-infected Anna, leaving Ellie an orphan.
Flashforward to our favorite duo in the season finale, who have finally reached the Fireflies and are able to piece together just how Ellie managed to be immune to that disastrous fungi.
As Marlene explains to Joel (as pointed out by Mashable, “Our doctor, he thinks that the cordyceps in Ellie has grown with her since birth. It produces a kind of chemical messenger. It makes normal cordyceps think that she’s cordyceps; it’s why she’s immune. He’s going to remove it from her, multiply the cells in a lab, produce those chemical messengers…and then we can give it to everyone. He thinks it could be a cure, Joel.” Basically, it’s as if Ellie got a vaccine as a baby to help her fend off the disease, and now they are looking to her to make the cure.
Of course, after the events of the finale, things are still a little complicated in that department, as that cure would require a piece of her brain, which would kill her. Also, the guy who would take a piece of her brain is dead, so that’s a dead end (sorry). It’s a pretty devastating conundrum that we will all have to see play out in season two of the drama…whenever that may hit our scenes.