Based on the comic book of the same name by Greg Rucka, The Old Gaurd stars Charlize Theron as Andromache of Scythia, a centuries-old immortal woman who, along with a group of fellow immortals, works as a mercenary using her vast knowledge from her long life in order to protect people. When a new immortal is revealed to exist, the team must work to protect her and evade capture by a pharmaceutical executive who wishes to discover what causes the immortals' miraculous healing powers.