Left Behind is the first single player DLC for the critically acclaimed survival horror game The Last of Us, developed by Naughty Dog. Set as a prequel to the main game, you take control of Ellie a few weeks before the events of the main story. One night while sleeping, Ellie is awoken and startled by her best friend Riley, a young girl who had left the boarding school a period of time ago after a confrontation with Ellie. To make up for leaving Ellie behind, Riley tells Ellie she has a surprise to show her and the two set off to sneak away from the school. As the two venture into a now abandoned Boston mall, events that will forever change everything for the both of them are set in motion.