Sandra Ann Lauer (born 18 May 1962), later Sandra Cretu, commonly known mononymously as Sandra, is a German pop singer who enjoyed mainstream popularity in the 1980s and early 1990s with a string of European hit singles, produced by her then-husband and musical partner, Michael Cretu, most notably "(I'll Never Be) Maria Magdalena" (1985), "In the Heat of the Night" (1985), "Everlasting Love" (1987), "Secret Land" (1988), "Hiroshima" (1990), and "Don't Be Aggressive" (1992).