Returning to his native Haiti (born in Port-au-Prince) after 12 years (originally nearly 20) of education and practice as an accredited psychologist in the United States, Jericho Drumm discovers that his twin brother, Daniel Drumm, the local houngan, is dying, a victim of a voodoo sorcerer who claims to be possessed by the spirit of the serpent-god Damballah. Just before he dies, Daniel makes his brother vow to visit Daniel's mentor, Papa Jambo. Jericho does, and becomes Jambo's student. After studying under the aged houngan for several weeks, Jericho gains a greater mastery of voodoo practices than his own brother, becoming a houngan in his own right. Papa Jambo then performs a rite that summons Daniel's spirit from the dead and joins it with Jericho's own. Having fashioned a worthy successor, Papa Jambo dies.
Taking the name "Brother Voodoo", Jericho challenges the priest, who goes by the same name as his god Damballah, and his cult. With the help of his brother Daniel Drumm's spirit possessing one of the cult members, Jericho removes Damballah's artifact of power (wangal), causing Damballah's snakes to turn on him and evidently destroying Damballah's cult. Brother Voodoo becomes Haiti's houngan supreme and champion, and establishes a sprawling mansion as a base of operations. He places the wangal in a safe, its combination known only to Brother Voodoo and his manservant Bambu.
Brother Voodoo encounters the scientist Baron Samedi and artificial zombies created by the terrorist-scientist group A.I.M.;the original Black Talon, Mama Limbo, and the Dark Lord Cult; and the houngan Dramabu. Having established himself, Brother Voodoo goes on to help other superheroes, including Spider-Man and Moon Knight, as well as the Jack Russell werewolf.