HBO's adaptation of the genre-defining stealth game, The Last of Us features the hardened survivor, Joel, and the razor-tongued, Ellie in the lead roles. Joel is tasked to deliver her to a group of Fireflies supposedly waiting for her at the Old State House. Their path is beset with difficulties, given that they live in a post-catastrophic world.

Related: The Last Of Us: Characters Who Could Appear In Season 2

Ellie and Joel are estranged at the beginning of their journey, but they get to know each other with time. They form a strong bond and by the end of The Last of Us season 1, they have the most-wholesome relationship in the series.

10 Ellie Asks If She's Family

Ellie and Joel in a car in The Last of Us.

Ellie (played by Bella Ramsey) asks Joel a defining question early on in The Last of Us season 1, episode 4 "Please Hold to My Hand" as they continue their cross-country journey.

Joel opens up to Ellie about his younger brother, Tommy's idealism, and the differences in their personalities. He says Tommy is the only family he has and therefore his motivation to keep going. When Ellie questions if she's family, Joel replies, "No, you're cargo." Ellie is saddened to hear Joel's answer because she considers him more than a smuggler who is trying to get her to the Fireflies.

9 Ellie Saves Joel

Ellie in The Last of Us.

In The Last of Us episode 4, when the duo arrives outside what appears to be the Kansas City QZ, a man stumbles into the middle of the road and asks for help. Joel immediately knows it's a trap, and he ends up crashing the truck through the storefront of a laundromat.

Joel confronts the attackers, while Ellie hides in a backroom. She springs into action when she sees Joel pinned to the ground, choking for air. She reaches for the gun she stole from Bill and Frank's house and sneaks up on the man. She shoots him in the back and frees Joel from his choke hold. Ellie saves Joel's life and proves that she too will go to any lengths for him.

8 Joel Asks Tommy To Take Ellie

Joel crying in The Last of Us.

Joel meets his estranged brother, Tommy at the Jackson settlement in The Last of Us season 1, episode 6 "Kin." The Miller brothers' reunion is tense, and their questionable past actions inevitably come up. Joel eventually opens up to his brother about enduring the trauma of losing his only child on outbreak day.

Related: The Last Of Us: Characters With Different Fates In The Show Compared To The Game

Joel delivers some of the most relatable quotes about failing Sarah, and about being afraid of repeating the past. He's scared of failing Ellie the way he says he did Sarah. In the end, he pleads with his younger brother to take the kid to the Fireflies because he thinks she will be safer with him. Joel cares about Ellie's life more than his and tells Tommy how much she means to her.

7 Ellie Stands Up For Joel

Maria giving Ellie a haircut in The Last of Us.

Tommy's wife, Maria briefly talks to Ellie in The Last of Us episode 6. She invites her over, presses her for a haircut, and starts to discuss Joel with her. Maria knows the truth about Joel's past, and so, she tries to warn Ellie about him.

Ellie jumps to Joel's defense and says he deserves a second chance just as Tommy did. Ellie suggests Maria examine her own moral code because she's holding Tommy and Joel up to different standards. At that moment, Ellie proves she is a daughter-like figure and brave enough to stand up to anybody for Joel.

6 Ellie Wants To Go With Joel

Ellie argues with Joel in The Last of Us.

In The Last of Us, episode 6 Ellie overhears Joel's plan to have Tommy drop her off in Eastern Colorado. While Joel feels he's incompetent to keep a girl of her importance alive, Ellie would rather go with him than his younger brother.

Ellie is heartbroken about Joel ditching her, and talks to him about loss and abandonment. Joel says Tommy knows the area better than him, and that he made the decision keeping her safety in mind. Unfortunately, Joel's unaware that Ellie considers him a new-found family, and everyone else pales in comparison.

5 Joel Comforts Ellie

Joel hugging Ellie in The Last of Us.

The Last of Us season 1, episode 8 "When We Are in Need," delivers the emotional weight and strengthens the protagonist duo's bond. In the said episode, Ellie kills the leader of the cannibalistic community, David in a burning steakhouse. She hacks him to pieces and stumbles out of the burning structure.

Related: The Last Of Us: The Worst Things That FEDRA Did

Joel finds Ellie outside and comforts her, saying, "It’s okay, baby girl. I got you." He last used the nickname "baby girl" on his daughter, Sarah in The Last of Us season 1, episode 1 "When You're Lost in the Darkness." These words are highly significant, and they go to show that Joel will protect Ellie like family.

4 Joel Saves Ellie's Life

Joel looking at Ellie in the operating room in The Last of Us finale.

At the end of The Last of Us season 1, episode 9 "Look for the Light," the duo is ambushed by the Fireflies while making their way through Salt Lake City.

When Joel wakes up, Marlene informs him that Ellie is set to undergo a fatal medical procedure, and they are a step closer to finding a cure. She forbids him from seeing Ellie and orders her men to escort him out. Joel risks his life and kills every Firefly to get to the operating room. He shoots the head surgeon and orders his staff to unhook Ellie. Granted Joel lies to Ellie about the medical fallibility of the procedure, but he acts like a parent who cannot bear to see their child sacrificed for the chance at a cure.

3 Joel Confronts Marlene

Joel carrying Ellie in The Last of Us.

Joel's final confrontation with Marlene in the finale turns violent real quick. She tries to press on him the ugly realities of the post-apocalyptic world and tells him how he won't be able to keep Ellie safe forever. He, meanwhile, wants her out of the kid's way.

When Marlene says Ellie lives in a broken world that Joel could have saved, he points out how performing a fatal surgery on someone else shouldn't be her decision. At that moment, Joel acts out of love and proves he isn't willing to lose his foster daughter for a potential Cordyceps cure.

2 Joel Opens Up About Sarah

Joel and Ellie hiking in The Last of Us Finale.

While Joel fails to protect Sarah, he finds a do-over in life with the utterly hilarious, and charming kid, Ellie. He drives her back to Jackson, and the duo hikes the last part of their journey. Joel opens up to Ellie in a way he never did before. He speaks fondly of Sarah, mentioning how they'd go on hikes before the outbreak.

Joel genuinely smiles as he recalls his time with Sarah. The conversation points out how Ellie has helped him cope with the traumatic stress of losing his child on outbreak day.

1 Joel Kept Ellie Out Of Harm's Way

Joel and Ellie in The Last of Us.

At the beginning of The Last of Us, Joel reluctantly took Ellie's responsibility because he'd struck a deal with Marlene. However, this no longer was the case by the end of the series. He genuinely began to see her as his daughter, and for the same reason, kept her out of harm's way.

Joel's affection for Ellie was born out of grief, and parental loss. He gradually began to accept her as his own and that's why he called her by the same term of endearment, "baby girl," that he'd use on Sarah.

The Last of Us TV series is available on HBO Max.

More: HBO's The Last Of Us: Most Heartbreaking Sarah Quotes