Brighten and fade the look of dark spots, acne scars, and hyperpigmentation with this potent vitamin C serum. Formulated with 15% vitamin C, Sunday Riley's C.E.O. Vitamin C Brightening Serum targets dullness and discoloration at the source while reducing the signs of aging. Skin looks and feels firmer and more plump with a youthful bounce and a radiant, even tone.