It's hard to imagine a world without Catherine O'Hara. The Toronto-born actress is always working, appearing in films that earn tons of money, tons of acclaim and frequently both. Her gift is comedy and whether a role calls for cerebral wit or slapstick clowning, O'Hara delivers. That may explain why directors such as Tim Burton and Christopher Guest cast O'Hara repeatedly in their films. After all, why mess with a winning formula?