Al Pacino — Turned Down Han Solo

Pacino was George Lucas's first choice for Han Solo in the original Star Wars. He passed because the script "confused" him. Harrison Ford took the role and it launched a career worth over $300 million, five Star Wars films, four Indiana Jones films, and cultural immortality. Pacino went on to make some of the greatest films ever (Dog Day Afternoon, Scarface, Heat, Scent of a Woman), so it's not like he suffered. But imagine Al Pacino saying "I know" to Princess Leia. The multiverse where that exists is a better place.