Ep 12. Scarlet Night

It's Halloween horror time when Archie discovers vampires in Riverdale. Veronica learns to her dismay that she is the Great Slayer who will cleanse Riverdale of the evil creatures. Veronica is already out to get the head vampire, Scarlet - not for being a vampire, but for taking Archie's attention away from her. In the end, Veronica battles the vampires and defeats Scarlet.