How Slick Hair Became the Supermodel's Answer to Beach Waves

There's hardly a better signifier of a sunny day well spent than a finger-combed mess of windswept waves, but leave it to the street style set to spark a party-ready hair trend that adds a bit of polished yin to all that beachy summer yang: slicked-back hair that conjures up lazy poolside chic and '80s-inspired power glamour in equal measure--while requiring little more than a fine-toothed comb and a dollop of gel to perfect. It all began with Kendall Jenner and Joan Smalls, whose minimalist hai...