When man-eating Titans first appeared 100 years ago, humans found safety behind massive walls. But the safety they have had for so long is threatened when a colossal Titan smashes through the barriers, causing a flood of giants into the city of Shiganshina. During the carnage that follows, soldier Eren Jaeger sees one of the creatures devour his mother, which leads him to vow that he will kill every Titan. He, Mikasa, and Armin enlist in the Survey Corps, that group is humanity's last hope.