What have the advertisers done right?

Pirates of the Caribbean advertising got very good job on it. on their Trailer, they talk about the introduction of the story and then use some of funny part or action part to make people foucas on the adverisiting. For example, on "At World's End" they talk about those main characters should go to save Jack. afte that, the story mvoe Pirates have crisis because england navy work with Devy jones, then they both want to destroy all of Pirates. This advertisment give people two things can makes people interest. first is why they want to save jack and second one is how can they figuer out the crisis. espically, the advertisment give people a funny infromation which the reason every characters save jack is not they miss jack. some of them want to kill him. those really makes people want to know why and go to watch that movie. that is why their advertismnet is done right.