In pretty much any form of storytelling medium, the script builds characters that the viewer either loves or hates, and then manipulates their lives, evoking various emotions. The word 'Character' is essentially a combination of stereotype, dress sense and often more importantly - personality.
I enjoyed watching the film 'Fight Club' not necessarily for the artistic style, or crime, but more for the in depth look at the main character's (Edward Norton) personality. In the film Edward plays a delusional schizophrenic, who is influenced by a guy called 'Tyler Durden' (Brad Pitt) but (SPOILER WARNING) at the end of the film the viewer realizes that the man Edward has been seeing is actually part of his personality. Its a relatively simple twist however it has a large impact on the viewer as the two personalities have been built up in detail for the viewer.
While you are watching, you almost feel sorry for Edwards Character, he lives in a boring life doing a boring job. When he meets the exiting and dangerous Tyler Durden you naturally want him to follow him because you want him to have a better life, want want want. You start caring about him.
As for Tyler you see him right from the beginning as being a dangerous exiting character, which is naturally interesting, you admire some of his actions and audacity, and at some bits he is portrayed as 'that guy everyone wants to be'.
The script is obviously important for these roles because without it you wouldn't get the same type of view of the characters lives. As well a job as Edward Norton and brad Pitt do to portray their roles, there is only so much you can learn from a characters actions in one scene. The way the two characters interact is pivotal in building their rapport with each other, and the viewer as a result.
The writers are using various different actions to show the viewer who the characters are. For example, with Tyler Durden, on the First scene that he is shown, he breaks many social norms, but in such an air of confidence that he gets away with all of them. At first he jokingly asks him self out loud, whether, when getting out of his window seat on an airplane he will give Edwards Character 'the Ass or the Groin'. He then goes to steal a nice car in public and get away with it.
This introduction gives the viewer an instant behavioral pattern with which to relate to his character, also known as a first impression.
For Edwards character the director shows the viewer parts of his life, and during the opening scenes, the low parts of his life. This first impression instantly tells the viewer that, that particular character has a sad life.
While as I said earlier, a lot of this character development cannot be achieved without the script, it is also worth noting that the acting and the appearance of the characters has a large part also. Both actors are very experienced and do a brilliant job of portraying their role convincingly. But more notable for me, the characters are dressed to emphasize their position.
For example, Tyler wears leather suits, jeans, and has bleached hair. He essentially dressed like a relaxed bad guy. Edwards character on the other hand, wears office suits, and has a well kept hair style for most of the film. These stereotype outfits allow the viewer to make a stronger link with their character.
The stories I find irresistible are often the stories where someone pulls through a hard time in their life. I'm not totally sure, maybe its because as much as I DO like to make jokes about humans, I actually care a lot about the people around me. This personal disposition means that films of the nature suggested, essentially do what I want them to do, hence why I like them. For example, I love the film Saving Private Ryan, the characters are brave and searching to help someone in need, this kind of story is the type I like.