Case in point: Kate Beckinsale's recent blonde makeover for her new film Jolt.
Along with going blonde, she also has a short bob. The new chin-length cut was styled in loose, messy curls. Combined, the new colour and cut is the most dramatic change Beckinsale has ever made to her hair since the one time she went blonde back in 2011.
There's a very good chance that Kate's new tresses are actually a wig. Just last week she was still rocking her long brown waves. The 45-year-old is currently filming Jolt - a millennial action flick in Bulgaria.
Watch: Kate Beckinsale shares her intense workout with A-List trainer Gunner Peterson