Omnibus tells the story of how black American gospel music evolved. The African tradition of slave songs was fused with the Anglo tradition of hymns when the slaves were converted to Christianity. With the abolition of slavery, gospel spread but the church continued to play huge part in its popularity until the forties and fifties when the music started to be played outside of the church. Using archive footage and specially recorded interviews from America, tonight's programme features Mahalia Jackson, Aretha Franklin, James Cleveland, Cissy Houston and Thomas Dorsey.