New to the U.S. (it launched here in May), but hugely popular in Korea, Mise En Scène has been the number-one hair-care brand there for 11 years, and should definitely be on your radar. This is its bestseller, a hair serum packed with seven different oils—argan, coconut, apricot, olive, camellia, jojoba and marula—that hydrates and nourishes hair to make it stronger, sleeker and more elastic. It also provides heat protection.