Ferryman who brought the dead across the rivers in Hades (6)
I believe the answer is:
charon
(Other definitions for charon that I've seen before include "Hell's mythical boatman" , "Ferryman on river of Hades" , "Boatman across the river Styx" , "Ferryman of dead (Gk. myth)" , "He ferries dead over Styx" .)