From the back of the book:
"Everybody knows there are no such things are monsters... You know better.
To the ordinary people of Victorian society, monsters are but silly superstitions or the cheap fiction of the penny bloods sold on the streets. But you are far from ordinary. You have seen horrors fearsome enough to stop a brave man's heart, and you have lived to tell the tale.
You are a Ripper - one of a secret band of monster hunters dedicated to saving humanity - and the horrors that stalk the night are your prey. To aid in this struggle, Rippers extract the essence of these monsters' powers and use them to enchance their own abilities. But be warned, by taking such horrific measure you risk losing your mind...or worse. Torn between the need for greater power and the threat of terrifying insanity, you must choose how best to fight the creatures of the night. Choose well, for if the Rippers fail humanity is lost!
Rippers is a Plot Point setting for the Savage Worlds Roleplaying Game."