Making a sequel in Hollywood might be the single most stress-inducing task for cast, crew, director and producer. Why? Because expectations are that the first film was, in all likelihood, well-liked and popular and thus by making a sequel you stand a chance to tarnish its legacy if not done right. You also run the risk of pissing off a considerably well-built fanbase that will ask for someone's head if the film fails to meet expectations. That's Hollywood for you. Most of the time the sequel doesn't come remotedly close to the original's freshness, but sometimes, in the case of these 10 classics, it turns out to be a landmark moment.