Spencer Tracy, Katharine Hepburn, and Louise Treadwell
The chemistry between Spencer Tracy and Katharine Hepburn in Woman of the Year was undeniable, but Spencer was already married to Louise Treadwell. The couple had met in their twenties and had two children together, but over the years, their relationship began to fray at the seams.
Spencer was a devout Catholic and it was against his faith to divorce, so the pair separated. Around that time, he and Katharine began their relationship. While all of Hollywood knew that Katharine and Spencer were together up until his death in 1967, she didn't speak openly about their partnership until her 1991 memoir, Me: Stories of My Life.