Potter's pioneering method of using music in his work emerged when developing "Pennies from Heaven" (1978), one of his biggest successes. He asked actors to mime along to period songs. "Potter tried out the concept himself by lip-syncing to old songs while looking into a mirror. Potter himself once revealed that, working on harnessing songs in his plays, he was most productive 'at night, with old Al Bowlly records playing in the background'". Potter had previously experimented with Bowlly's voice in "Moonlight on the Highway" (1969).