The development of The Last of Us, an action-adventure survival horror video game, began after Uncharted 2: Among Thieves' release in October 2009. Sony Computer Entertainment published The Last of Us on June 14, 2013 for the PlayStation 3. The three-year development, led by studio Naughty Dog, was kept secret for the majority of development. In the game, players assume control of Joel, tasked with escorting the young Ellie across a post-apocalyptic United States, in an attempt to create a potential cure against an infection to which Ellie is immune. Creative director Neil Druckmann was inspired to include Infected as a main feature of the game after discovering the Cordyceps fungi. His story, set twenty years after the outbreak starts and much of civilization is destroyed, explored the possibility of the fungi infecting humans.
Though Ellie was initially intended to be Joel's daughter, the team found this to be too limiting in terms of further character development. The team chose Troy Baker and Ashley Johnson to portray Joel and Ellie, respectively. Providing both the voice and motion capture of the characters, Baker and Johnson assisted the team to develop the characters and help refine the story. The relationship between Joel and Ellie was the central focus of the game, and all other elements were developed around it. Various other characters were influenced by the story progression, ultimately becoming completely different from the initial vision.
The Last of Us features an original score, composed by musician Gustavo Santaolalla. Known for his minimalist approach to composing, Santaolalla was contacted early in development. Naughty Dog took a similar minimalist approach to other elements of the game, including the action, sound design and art design. The sound department began working early on the sound of the Infected, in order to achieve the best work possible. A similar direction was taken by the art department, whose designs influenced other elements of development. Naughty Dog overhauled their game engine for some elements, particularly lighting and animations.