In the world of improvisation, there’s a golden rule. If someone declares something, you’re supposed to treat it as a fact and play with it. So if two people are improvising and one says, “Look at that dog,” you’re supposed to acknowledge the dog somehow and play with that idea. What you can’t do is say, “That’s not a dog. That’s a giraffe.” In other words, you have to add, not deny, what each person says.
The movie sequel industry should work that way too, but when it doesn’t, it creates a horribly disappointing experience. Just look at the difference between “Mall Cop” and Mall Cop 2.” In the first “Mall Cop,” the hero is a down and out mall security guard who has the support of his mother and slowly develops a relationship with an attractive mall worker. By the end of “Mall Cop,” the hero has saved his attractive co-worker, defeated the bad guys, and become a hero of the mall.
Despite the silliness of the story, “Mall Cop” is a funny and well structured story. Then they got the bright idea of making “Mall Cop 2” and what’s the first thing they did? Within the first five minutes, the hero gets divorced from the attractive girlfriend he wooed in “Mall Cop” and his mother gets killed by a milk truck.
Suddenly we’ve gone from the hero having a beautiful girlfriend who becomes his wife to suddenly being divorced and a loser again. Then we’ve gone from his mother supporting him emotionally to seeing her die within minutes of “Mall Cop 2.” Essentially “Mall Cop 2” takes the happy ending of “Mall Cop” and wipes it out completely. The result starts “Mall Cop 2” off on a sour note that it never recovers from.
The rest of “Mall Cop 2” focuses more on defeating the bad guys and nothing else. Like most sequels, “Mall Cop 2” eliminates the emotional element that made “Mall Cop” so successful and replaces it with more mindless action that can’t substitute for a truly engaging story.
Sequels need to add to the story, not destroy it. Look at how the “Alien” franchise fell apart after “Aliens.” Look at how the “Terminator” franchise fell apart after “Terminator 2.” When you substitute mindless action for a well-structured story, you get an expensive mess, which Hollywood keeps repeating over and over again.
In your own script, make sure each element you introduce builds and adds to your story. If it doesn’t help your story, it doesn’t belong. If it contradicts earlier information for no good reason, it definitely doesn’t belong.
Don’t make the same mistake over and over again like Hollywood does (over and over again). Heed the golden rule of improv and build on information rather than replace it. Your story will be stronger and more interesting as a result.