Naughty Dog has unveiled Left Behind, the first piece of story-based DLC for survival horror title The Last of Us.

At today’s PlayStation 4 launch event in the US, Naughty Dog explained that Left Behind is set before the events of the main game, and follows Ellie and her friend Riley as they explore an abandoned shopping mall.

Ellie is attending a military boarding school in Boston, and Riley is her mentor of sorts.

If that name sounds familiar, it’s because Riley has a big role in The Last of Us' comic prequel, The Last of Us: American Dreams.

Left Behind is expected to be out in early 2014, and is included in the game's Season Pass.

See below for the teaser trailer.

Ellie the star of The Last of Us story DLC Left Behind