By Olivia Bahou
Updated Mar 23, 2016 @ 7:30 am
Michelle Monaghan - Lead
Credit: Anthony Harvey/Getty Images

Happy birthday, Michelle Monaghan! The Gone Baby Gone actress turns 40 today, and she hasn’t aged a day since she bust onto the scene in the TV series Young Americans back in 2000.

From brunette to blonde and back again, the “banging” actress has experimented with fringe, retro waves, and sleek straight styles. The hair chameleon is equally as versatile onscreen, starring in everything from Nicholas Sparks’s novel-turned-film The Best of Me to crime series True Detective, adventure-comedy Due Date, and thriller Mission: Impossible III.

In honor of the big 4-0, take a look back at this multitalented star’s transformation through her years in Hollywood.