It has been five years since Laura and Carmilla vanquished the apocalypse and Carmilla became a bonafide mortal human. They have settled in to a cozy apartment in downtown Toronto, Laura continues to hone her journalism skills while Carmilla adjusts to a non-vampire lifestyle. Their domestic bliss is suddenly ruptured when Carmilla begins to show signs of "re-vamping" – from a fondness for bloody treats to accidental biting – while Laura has started having bizarre, ghostly dreams. The couple must now enlist their old friends from Silas University to uncover the unknown supernatural threat and save humanity – including Carmilla's.
Two young students at a prestigious prep school for girls are assailed by an evil, invisible power when they are stranded at the school over winter break.