Maggie Siff was 32 in Michael Clayton when she played the character 'Attorney #1'.
That was over 17 years ago in 2007.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 49, and has starred in 11 movies in total, 10 of those since Michael Clayton was released.
In Michael Clayton, I think Maggie Siff looks: