Happy birthday, Scarlett Johansson! The new mom to 3-month old Rose Dorothy and action star celebrates a huge milestone: her 30th birthday. Johansson made her film debut at the tender age of 9, but it took her role as Grace McLean in The Horse Whisperer to capture the attention of Hollywood. She went on to land a leading role in Lost in Transition, which earned the sultry beauty her first Golden Globe nomination.
Since then, the two-time InStyle cover girl has paved her way to becoming one of the sexiest-yet-glamorous celebrities to star in big-budget blockbusters, independent films, and Broadway shows. Like her challenging array of roles, the Tony award-winner isn't afraid of chopping her mane -- even mullets! In honor of Scarlett Johansson's birthday, take a look back at her changing 'dos through the years.