Spend enough time seeing huge billboards of your own face plastered over practically every city in the world and surround yourself with "yes" people who by their very nature are required to be fawning and sycophantic, then chances are you'll end up with an ego the size of the Hollywood hills.
While this doesn't happen to everyone who breaks into the film industry and heads for stardom, some actors seem to struggle more than others when it comes to keeping their heads out of the clouds. Having played the hero and saviour perhaps once too often, or the beautiful and irresistible leading lady every man wants to bed, sooner or later their vanity gets the better of them and the next thing you know hundreds of millions of dollars have been pumped into their personal "pet project".
The outcome isn't always a complete disaster, but more often than not the movie that ends up on cinema screens says a lot more about the psychological make-up of the A-list actor who pushed it into production than it does about decent filmmaking. Rather than telling an interesting story with rich and rounded characters, what audiences actually see is the same actor in scene after scene after scene, lavishing the attention of the camera lens at the expense of everything that makes films entertaining.
The following list covers ten of the most cringe-worthy vanity projects ever produced in the history of cinema - watch them only if you have the stomach for a shameless procession of ego-driven drivel.