you know, i have this theory according to which, besides gemini and maybe saggitarius, no other sign can truly act - meaning completely disguise their personality.
another case in point - easy a. it works and it's fun because they picked the scorpios to do it. i mean - taboos, secretes, sex, gossip, did-she-do-it-or-didn't-she - that's scorpio territory, complete with drama and a facade of snarkiness which hides a lot of sensitivity. because, y'all, scorpios rival pisces in the feeling department (this is why piscean bruce willis always plays the savior). and emma stone is a scorpio and so is woodchuck todd (which should have been meerkat todd, shiny lulz. that's trufax - i've read it on imdb so it must be true) - while BFF rhiannon is an aries (and martian badassery collides so, duh, no wonder they couldn't be friends. they're competing).
...and we know this is a scorpio movie from the opening line "The rumors of my promiscuity have been greatly exaggerated." says olive. you know, because we all expect scorpios to do it with everyone. which they don't but they look like it anyway and they will play along with that because it's the power trip they get. also - the scarlet letter, written by a cancer - and being inspired by it too. you know, it's totally the sort of book water signs would read and act accordingly to its teachings.
and let's not forget the whole religion thing. yep, that's also scorpio territory.
...and, somehow unsurprisingly, the writer of the movie is a libra. but i think he had in mind something more on the "les liaisons dangereuses" side. we're into that type of intricate and convoluted plots.