The 37-year-old American actress posted the following photo on Instagram with the caption: "Someone got a haircut courtesy of @renatocampora #hair #genius #brigittebardot #60s #fashion #iloveitsomuch"
Now this look has gone straight to the top of our "Celebs with REALLY amazing hair" list. It's very Brigitte Bardot, don't you think?
The best thing about this style is it's completely versatile - you can wear it down and wavy like Chastain, swept up into a sleek ponytail or do the dishevelled braid trend like the Braveheart-inspired styles on the Giles Spring/Summer 2014 catwalk.
It's Chastain's understated elegance that makes this style less edgy (the fringe is wispy not blunt) and more luxe. And the soft layers are how exactly how to nail voluminous red carpet-ready hair.
With her tresses looking this good, the pressure of finding the perfect dress is definitely off. Plus, Jess knows exactly how to accentuate her red tresses and porcelain complexion - a popping pink lipstick.
LOVE JESSICA'S STYLE? Take a look through this gallery of photos all about the Hollywood lady working the red carpet. She never fails to look completely stunning.
MORE! Watch all the latest news on Jessica Chastain right here.