With an effortless emotional delivery, Gregory Isaacs remains one of reggae's greatest seducers. But his deep catalogue also reveals righteous political tracks, like the nyabinghi-spiked “Warrior” and the pacifist plea “Black a Kill Black.” Lilting horns sweeten “Set the Captives Free,” and against the digital drums of “One Man Against the World,” Isaacs' purr is both defiant and convincing.