Early in his career, Woody Allen famously cast himself as the male lead in his movies, making a name for himself as an actor in Bananas, Annie Hall, Manhattan, and many others. As he grew older, Allen kept the neurotic persona but has occasionally charged other actors with the role, including John Cusack, Will Ferrell, and Jason Biggs.
For his upcoming release Whatever Works, Allen has once again thrown the role onto someone else, casting Curb Your Enthusiasm's Larry David as the lead. While it was a bit of a stretch for someone like Ferrell to take up Allen's mantle, with just a little digging it's clear that this role won't be too difficult for David. In fact, their similarities are pretty stunning. See
Whatever Works: Woody Allen Casts His Twin.