Fresh off of her recent Cosmopolitan cover, actress Hilary Duff has dyed her hair a mermaid blue. The formerly blonde star revealed the change on her Instagram page earlier today. Hilary had her hair dyed at the Nine Zero One Salon in Hollywood. The 27-year-old thanked the salon for turning her into a mermaid. Hilary is not the only star to recently switch up her look though. January Jones revealed a pink hairstyle several days ago.