All three books of the Black Current in one complete volume

Yaleen's life has always been defined by the Black Current, a strip of black running along the center of the river that separates the eastern bank from the mysterious western side. The Current's nature is indefinable, but Yaleen's people sense that it is alive and powerful, as it allows only women into the river and brings madness and death to men who enter more than once. Longing for the freedom being a river-woman gives, Yaleen drinks of the black current and joins the River Guild. But when her brother Capsi discovers a way to cross to the forbidden western side, Yaleen is caught in the middle of a battle that could end the world.