Before they became a defining pop duo of the mid-1960s, Sonny & Cher emerged from the restless, transitional landscape of early rock and roll, when the industry was shifting from the dominance of teen idols toward more experimental studio-driven sounds. Their eventual chemistry was rooted not only in their contrasting personalities and voices, but also in the musical apprenticeship each underwent separately in Los Angeles, a city rapidly becoming the epicenter of American pop production.