2. Christian Bale
When it comes to dramatic makeovers, it’s hard to beat Christian Bale. In 2004, the English actor’s appearance in psychological thriller The Machinist was downright skeletal. The normally fit actor dropped a startling 63 pounds to play insomniac machine worker Trevor Reznick. What’s more, a mere five months later Bale had put all the weight back on – plus 30 pounds of pure muscle – to play buff superhero Bruce Wayne in Batman Begins.