Given Hadid's recent history with hair color, it's hard to say whether or not her black hair is temporary or permanent, but one thing is for sure: Hollywood's elite have embraced drastic changes this season. For example, Kendall Jenner went blonde during the London leg of Fashion Month, then went back to brunette right after. Millie Bobby Brown just ditched her brown hair to join the blonde bandwagon , and so did Mila Kunis, who traded her trademark dark locks for platinum hair with blue tips . Hadid's latest transformation is further proof that you don't have to stay married to one look — now we wait to see what color she rocks next...