It's fair to say acting is a profession that can see a huge contrast in personalities. Some actors are genuinely nice people who realise they are in a privileged position, while others like to keep a low-profile and just get on with their job. On the flip side, however, there are those who are incredibly hard work, using their power and reputation to belittle others and make everyone else on set uneasy. There are a fair few of these egotistical multi-millionaires to choose from. This list looks at the 10 most difficult actors who are working today - Marlon Brando would walk into the top three were he still alive - and the various examples of their unpredictable behaviour. Some have taken method acting to a new level, some are perfectionists who don't suffer fools gladly, while others are just downright nasty pieces of work. The likes of Jennifer Lopez, Julia Roberts, Dustin Hoffman, Tommy Lee Jones and Wesley Snipes can think themselves lucky to have avoided the cut, among numerous others - they came awfully close. It's worth stressing that some of the names on this list are extraordinary talents who would not have forged the wonderful careers they have if it wasn't for their rather complex behaviour. Still, that doesn't mean they are not an absolute pain in the neck to those working alongside them though. Let's get started...