Whentheworldishitwithanaturallyoccuringvirusthatspreadsamongalllivingthings,humansbegintoturnintoinsatiablezombies.Inablink,theworldasweknowitcollapses.Furthermore,thefewremainingsurvivorsareunabletousetheavailablefoodresources.Theythereforedevelopanewcroptosupportthemselves.Survivorsdependononeprofession,theironlyhope;someoneinthisprofessionmustbravethedangerstosendandrecievefoodandpackagesofnecessities.ThesepeoplearecalledRiders.