Remember when Brad Pitt wore a beanie for so long that it made dudes start buying beanies so they could look like Brad Pitt? Well, this is just hairdresser speculation, but I'd venture to guess that Pitt's hat phase/craze was a happy accident resulting from his follicle transplant surgery. Now the speculation continues as fans wonder if he got extensions for his latest upcoming role in World War Z. 

It remains a mystery whether or not one of Hollywood's most notorious pretty-boys was just blessed with an immovably youthful hairline, but regardless the length is likely his own. The highlights, on the other hand, are of course artfully faked. While we await the trailer for World War Z, have a gander at the assortment of hairstyles the icon has rocked over the decades. Enjoy!