The Real Cool KillersOne of the towering figures of the black literary tradition. Henry Louis Gates, Jr The night's over for Ulysses Galen. It started going bad for the big Greek when a knife was drawn, then there was an axe, then he was being chased and shot at. Now Galen is lying dead in the middle of a Harlem street. But the night's just beginning for detectives Grave Digger Jones and Coffin Ed Johnson. Because they have a smoking gun but it couldn't have killed Galen,