Maybe just seeing fellow Avengers Captain America (Chris Evans) and Iron Man (Robert Downey Jr.) in the fight of their lives against each other in Captain America: Civil War is enough to thrill you. The two "good guys" and usual friends are so vicious toward each other in the film's fight scene that you don't even know who to root for — or who's actually stronger. But there's a moment during that hand-to-hand brawl where Cap says one thing that firmly puts you on his side — if you remember that you've heard it before.
When Cap and Tony are going at it, just beating the crap out of each other, Tony gets in a shot at Cap's perfect face. Cap, looking like a boxer about to go down, gamely tells Tony with a bloody mouth, "I can do this all day."
You've heard it before, out of Cap, but in very different circumstances. It was several Marvel movies ago — in 2011's Captain America: The First Avenger, to be exact. Before Cap was Cap, he was puny little Steve Rogers, a Brooklyn guy so small and wimpy he keeps getting rejected by the Army. Before he undergoes the treatment that makes him the sexy supersolider he is today, Steve gets into a fight, and though he can't win, he proves how scrappy he is when he says the epic line.
It's a nice little callback that's both a wink to the fans and acknowledgement that inside, Cap is still the same Steve Rogers, a guy from Brooklyn with a lot of heart.