Since debuting with the Top Ten U.K. hit “Your Love Is King” (1984), Sade have remained, across four ensuing decades of intermittent activity, shrewd synthesists of classic jazz, cutting-edge R&B, and mature pop. Although they’re known most for stylishly seductive ballads, including the international hits “Smooth Operator” (1984), “The Sweetest Taboo” (1985), “No Ordinary Love” (1992), and “By Your Side” (2000), they’ve also recorded poignant songs regarding slavery, immigration, parenthood out of wedlock, and everyday struggles, often through Sade Adu’s third-person narratives.