Spencer Tracy was one of the biggest stars of golden age Hollywood. He brought a subtle, naturalistic style to even the biggest roles, earning Oscars and big numbers at the box office in the process. In his later career, he appeared in several critically acclaimed movies with strong, sometimes controversial, social messages—Guess Who's Coning to Dinner among them. His private life, though, was far more complicated: a lifelong struggle with alcoholism and a string of affairs with women and men left the Catholic Tracy constantly guilt-ridden. No less complex was his decades-long relationship with Katherine Hepburn, with whom he'd be forever associated.