The MCU began in 2008 with the first Iron Man movie, and it has been adding new characters and stories to the series ever since. The first indication that this superhero franchise would exist in a shared universe came in the post credits scene during Iron Man, when Nick Fury shows up to tell Tony Stark about The Avengers Initiative. The end goal for this team of superheroes was then revealed at the end of Avengers Assemble, when Thanos was shown to be a key figure in this universe. His main goal was assembling the infinity stones and using them for his own villainous ways.