"The Whisper Network – Before the internet there was the laundry line" explores the history of "Word of Mouth" marketing before social media. It focuses on the 1920s and 30s, when companies like Procter & Gamble realized that women didn't trust ads, but they trusted their neighbors. Author Sarah Voice details the invention of the "Soap Opera"—radio dramas created solely to sell detergent to housewives—and the orchestrated "whisper campaigns" where paid actors would ride elevators or sit in parks, loudly praising a product to "overhearing" strangers. "The Whisper Network" is a masterclass in analog virality. It shows that the mechanics of influencers and viral trends existed long before Instagram, rooted in the timeless human habit of gossip and the credibility of a recommendation from a "friend."