After 10 years of storytelling and world-building, the MCU has become the epitome of franchise filmmaking, and there’s some pretty genius foreshadowing in the Marvel Cinematic Universe that helped get to this point. Even when Iron Man first hit theaters in 2008 and Marvel Studios barely had an idea of how large their franchise would become, they were dropping hints about a bigger universe. From that film on, every addition to the MCU continued to push toward a boiling point, and that happened in Avengers: Infinity War.
Marvel Studios hid clues about Infinity War in plain sight for more than a decade, and although most of them were caught by obsessive fans, there were still plenty of surprises left. The Infinity Stones themselves were teased, introduced, and explained across multiple films, and Thanos made several cameos before taking a lead role. Not all foreshadowing was quite so obvious, however. Even seemingly innocuous lines of dialogue throughout the MCU pointed towards the destiny that would one day arrive.