Several hundred years ago, the humans have encountered a new enemy the “Titans”. The titans have pushed humanity to the brink of extinction. The remaining survivors built extremely high walls to protect themselves from the Titans and for 100 years they lived in peace. Until one day a colossal titan appears and destroys the outer walls allowing the other titans to get in, resulting in a massacre. One of the victims was Eren’s mother who was eaten alive. Eren escapes and vows to wipe the earth clean of Titan.