Durarara!! Vol. 2

After saving a mysterious girl with a scar on her neck, Mikado finds himself chased by the headless rider. Shortly after this incident, the Dollars first meeting, suddenly organized by their mysterious leader, takes place in Ikebukuro and will become the field of a supernatural phenomenon, revealing the truth behind the entire masquerade.
But six month after the big Dollars meeting, even if Ikebukuro has at first glance returned to normal, some troubling events are occurring again. Rumors about a strange being called "the Slasher" and an old gang named " the Yellow Scarves" are beginning to spread out. Mikado, Masaomi and Anri are facing new mysteries related to their respective pasts.
Who is the Dollars leader? And this so-called Slasher? And why are the Yellow Scarves reappearing after a long break?