Celebs Who Swing: 20 Celebrity Couples In Open Relationships

19. Katherine Hepburn and Spencer Tracy

Technically, Katherine Hepburn was the side piece in Spencer Tracy’s open relationship, as he never divorced his first wife, and never breathed a word about their relationship publicly. After Tracy’s wife passed away in the 1980s, though, Katherine spoke of their decades-long fling, including moving into his house when he was on his deathbed to help care for him.