(Warning - possible SPOILERS for Captain America: Civil War lie below. Proceed with Peggy Carter-like caution...)
If there's one thing you should never do in a Marvel movie or series-related context, it's underestimate Peggy Carter. Sure, starting a fight with the Hulk'll most likely get you crushed into a miniature version of yourself, and getting into a drinking contest with Cap'd be magnificently unwise, but at the end of the day, you'd at least have a chance.
Underestimate Agent Carter, though, and you're already toast.
Knowing that, then, perhaps it shouldn't be quite as much of a surprise as it first seems to see Hayley Atwell - Peggy Carter herself - on the set of Captain America: Civil War - despite the movie seemingly featuring her older self's funeral, as we did this week.
After all, as the images below - posted by Atwell herself to her Twitter account - prove:
Peggy Carter Is Always Awesome
All of which began with a single Tweet:
Which was swiftly followed by Atwell distracting Chris Evans with tablet-based gaming in-between takes:
Along with the film crew...
Before things progressed to her taunting The Falcon...
And, of course, making awesomely stupid faces while he looks casually handsome in the background...
The most intriguing part of Atwell's behind-the-scenes Twitter frenzy, though?
She Might Just've Revealed She Was Shooting a Scene
Now, sure - it's entirely possible that Atwell was just saying hi to an old friend, as part of a purely-for-fun set visit, and that her hanging with Peggy's makeup specialist doesn't actually mean she'll be in Captain America: Civil War.
Except, of course, that this is the third - and potentially final - part of Cap's solo cinematic journey we're talking about - and Peggy Carter is a huge part of his history. If we really are set to see Peggy's present-day, older self pass away, it doesn't seem out of the question that we'll also see a flashback to her and Cap's brief romance - or possibly even to a key moment in S.H.I.E.L.D's history.
Plus, if you take a closer look at those Tweets, it sure does look as though Atwell was on set for more than one day...
All of which really just goes to show you:
YOU SHOULD NEVER, EVER UNDERESTIMATE PEGGY CARTER
And, also, of course, that Hayley Atwell is awesome, which is heavily related.
What do you reckon, though?