The following contains spoilers for The Last of Us Season 1, Episode 9, "Look for the Light," which debuted Sunday, March 12 on HBO.

The Last of Us has showcased a cross-country trek through post-apocalyptic America after the world is overwhelmed by the mindlessly ravenous following a mass fungal contagion. With the ninth and final episode of Season 1, Joel and Ellie’s journey comes to an end -- but their harrowing ordeal is far from over. And as Joel contemplates his close dynamic with Ellie, he must make an impossible decision to determine both of their futures.

In a flashback sequence, a pregnant woman named Anna runs for her life across the countryside, taking refuge in a large house in the middle of an open field while being pursued by a clicker. The clicker breaks into the room and bites Anna in the leg before she stabs it to death -- and gives birth to her daughter Ellie immediately thereafter from the stress induced by the struggle. That night, Marlene and the Fireflies arrive at the house where Anna entrusts Ellie to Marlene’s care, along with her knife. She begs Marlene to put her out of her misery before she succumbs to the infection, with Marlene reluctantly complying.

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last of us e9 anna in the forest in a yellow dress

Back in the present, Joel and Ellie arrive in Salt Lake City, where the Fireflies have relocated their medical facility. The pair enter an unfinished skyscraper to scope out the area, with Joel noticing Ellie has become much more withdrawn since her ordeal with the cannibals who nearly butchered her. Ellie notices a giraffe eating on some of the vegetation growing alongside the building. Joel helps her feed it while he contemplates just going back to his brother Tommy instead of proceeding to the Fireflies as planned.

But when Joel and Ellie near the hospital the Fireflies are based out of, they are incapacitated by stun grenades. Joel awakens in their custody, observed by Marlene and armed guards. He learns that Ellie is being prepped for surgery to remove the part of her brain producing the chemical making her immune to the fungal infection, with the surgery expected to kill her. When Marlene has her guards forcibly escort Joel from the premises, he overpowers and kills them before setting out to save Ellie.

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Battling his way through the Fireflies, Joel mercilessly finishes off even those who surrender to ensure that there is no one left alive aware of what Ellie is capable of. Joel enters the operating room where he finds Ellie under anesthesia and stops the surgery, sparing the nurses but gunning down the surgeon when he refuses to comply. Carrying the unconscious Ellie in his arms, Joel is intercepted by Marlene in the hospital’s parking garage; she begs him at gunpoint to relinquish Ellie in order to produce the planned vaccine. Joel refuses this ultimatum and kills Marlene when she lowers her guard, driving away from Salt Lake City with Ellie.

She gradually regains consciousness as the two continue down the highway. Though Joel claims that the Fireflies were unable to develop a cure from her and other prospects and have stopped trying, Ellie notices that they left the hospital without recovering her clothes, poking holes in Joel’s story. Joel and Ellie return to Wyoming before their car breaks down and hike the rest of the way to Tommy’s mountainside community, with Joel assuring he told a skeptical Ellie the truth about what happened. They try to move on from their latest ordeal together into an uncertain future.

Created by Craig Mazin and Neil Druckmann, The Last of Us is available to stream on HBO Max.