V

Now, as far as creating the specific conflict for your main character, some obstacles are external, some internal, some both, but the best obstacles are those that are created by the characters themselves. This is why establishing very specific character flaws is so important in the first act: hubris, doubt, narcissism, jealousy, overconfidence, etc... because it is with the character's own flaw(s) that will get him or her into even more trouble. And more trouble is exactly what you want - self induced trouble is a recipe for success. To put it another way, it is…

This is the meat and potatoes portion... AND the most difficult part of writing a screenplay. Most mediocre and flawed screenplays are plagued by slow or meandering second acts. Keep in mind the main tension - and that your character should always be on the path to resolving that tension.