Jessica Biel at the Orange British Academy Film Awards

There are some who just shouldn't go blonde.  With colors and hues being divided into warm and cool, the best rule of thumb is to remember that with hair and makeup, the two different tone categories do not blend well together.  Jessica Biel has a pink cast to her complexion, making it appear rosy, and that cool tone just doesn't look good against the warm, orange cast of her new hair color.