20 Fails That Nearly Killed The Marvel Film Universe

18. Keira Knightley As Peggy Carter? (Captain America: The First Avenger)

The original casting for Captain America's fleeting love interest Peggy Carter came down to four actresses: Hayley Atwell (who eventually snagged the part), Alice Eve, Emily Blunt and...Keira Knightley. Why It Would've Ruined The MCU: While we can imagine any of the other actresses ably playing the role of Carter, Knightley sticks out like a gigantic, sore thumb here. Sure, she's got the whole posh British thing going for her, but we can't really see her having the personality to pull the part off, and also, it's easy to imagine her having a total lack of chemistry with Chris Evans. Eve and Blunt are colourful, charming enough personalities that we think they could've nailed the part, but Knightley? It would've been a classically awful bout of miscasting, and one that fanboys would likely have been complaining about forever more.