We don’t just throw around the term “A-list,” so believe us when we say this conditioner has serious star power. Created by Beverly Hills stylists Amanda George and Neil Weisberg, it’s a cult favorite—thanks in part to the duo’s client list. Now you know how the likes of Charlize Theron, Kate Hudson, and Victoria Beckham get hydrated, shiny, and supple hair that’s never heavy or dull.