Pioneering journalists in the late 19th and early 20th centuries exposed societal ills through groundbreaking investigative techniques. Figures like Nellie Bly, Ida B. Wells, and Upton Sinclair used undercover reporting, data analysis, and vivid storytelling to shed light on issues like mental health, racial injustice, and labor exploitation. Their work had a profound impact, leading to reforms and shaping the role of journalism as a force for social change. These journalists faced ethical challenges and personal risks, but their legacy continues to inspire modern reporters to hold power accountable and give voice to the marginalized.