However, that fragile calm is soon shattered when a colossal Titan manages to breach the supposedly impregnable outer wall, reigniting the fight for survival against the man-eating abominations. After witnessing a horrific personal loss at the hands of the invading creatures, Eren Yeager dedicates his life to their eradication by enlisting into the Survey Corps, an elite military unit that combats the merciless humanoids outside the protection of the walls. Eren, his adopted sister Mikasa Ackerman, and his childhood friend Armin Arlert join the brutal war against the Titans and race to discover a way of defeating them before the last walls are breached.