"The thick, low-lying fog covered the contours and waterways of the swamp. Only mature trees and shrubs were visible above the milky gray mist. Darkness was beginning to fade in the early-morning light, creating the surreal landscape of a nightmare." So beginsStanding at the Scratch Line, a breathtaking journey through thirty years of the African-American experience in America in a brilliant debut novel by Guy Johnson.          The story opens in 1916 in the steamy bayous of Louisiana. Young LeRoi "King" Tremain and his uncle Jake attempt a raid on a rival family's compound. In doing so, Jake dies, but not before LeRoi kills two corrupt white deputies. Forced by his family to leave everything he knows until the heat dies down, LeRoi embarks on a vivid adventure that first takes him to France during World War I, where he finds it is just as easy to kill vicious, bigoted U.S. soldiers as it is to kill Germans. Dubbed "le Roi du Mort"-the king of death-by the French because of his coldhearted, machinistic killing on the battlefield, King returns to America an ambitious man. Driven to create a family dynasty much like the one he was forced to leave, he battles the Mob in Jazz Age Harlem, fights the Ku Klux Klan in Louisiana, and outwits crooked politicians trying to control a black township in Oklahoma. Those who cross him are left bloodied, bruised, or dead.          Along the way, he marries Serena Baddeaux, a woman strong enough to stand by King's side,  and who matches his determination, courage, and grit. Though more concerned with skin color and social standing than with the truth, she nonetheless knows no boundaries when it comes to protecting her family.          Standing at the Scratch Lineis a sweeping novel that heralds the arrival of Guy Johnson, a bold new voice in fiction. In King Tremain, Johnson has created one of the most stalwart characters to walk the pages of fiction, as well as a brutally honest depiction of the African-American experience during the first half of this century.