The best beauty looks this week showcased great hair. "Mad Men" starlet Kiernan Shipka sported an age-appropriate updo, while "Iron Man 3" actress Rebecca Hall proved that she has the best effortless summer waves.
And the worst looks of the week were hair-raising, too -- Kelly Osbourne may have forgotten that she has bright purple hair when she applied too much self-tanner and Uma Thurman (who was looking stellar just last week!) may have skipped out on shampooing and/or brushing her hair before hitting the red carpet.
Click through the the slideshow to see which stars shined this week and which ones missed the mark. Do you agree? Tell us in the comments below!
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