Sienna Miller [1] is best known as a blond bombshell who rarely strays from her golden roots. That's changed for her new role, though. The actress debuted freshly dyed red locks [2] on the set of her new movie, American Sniper, on Tuesday, just weeks after we last caught a glimpse of her signature look at Kate Moss's star-studded Topshop launch [3]. The actress isn't a complete stranger to the fiery shade — in January, Sienna's hair was red during her bikini-filled family vacation [4].

With her new look front and center, Sienna has been busy filming scenes with her handsome costar Bradley Cooper [5], who has also experienced a transformation for the movie. Earlier this month, Bradley showed off his new beefy body [6] before he suited up for the Met Gala [7]. Keep reading to see Sienna and Bradley's new snaps!