9. Iron Man 2
It can be a little tough to get a handle on where you actually are in the grand timeline of the MCU. But Iron Man 2 made the genius decision to take audiences immediately back to where the first Marvel Studios big hitter had left off, before eventually propelling the story forward a few months.
Focusing on said opening, though, we find Mickey Rourke's Ivan Vanko watching on in Russia as Tony Stark's Iron Man revelation unfolds before the world's eyes and his former Stark Industry employee father's life devastatingly slips away before his own. What follows is a sequence that shows the intense figure forging his own arc reactor, setting in motion the eventual collision between the two down the road.
With all the hype swirling around this first MCU sequel and Rourke's seemingly significant role within it, an opening as emotionally charged and this focused on fleshing out Stark's nemesis instead of the main man himself suggested exciting things were on the horizon.
If only the rest of the average follow-up delivered the goods in a similarly impactful fashion.