Regardless of the medium for which we write plays, they are fiction. Even when dramatic works are fact-based, details of time, place and purpose make it impossible to duplicate events precisely. Still, if a subject is important enough to write about, you want your audience to believe your story. Basing it on reality and facts gives your work credibility. You are an expert on you, so your feelings, the people you know, and your experiences are your best resource. But if you want to write on a subject you know nothing about, you can study and write what you learn. 

 

Your public library and the internet can offer unlimited, free information on everything from astronomy and politics to cosmetic surgery. Research can expand your knowledge and experience so you can handle new subjects accurately.  For example, let's say you want to write a script which involves legal issues but you know little about the law. A public library is a good place to start. And you can find answers to some legal questions simply by typing them on Google. There are even web sites where you can ask an attorney.

 

Other resources include institutions, such as your state bar association. Practitioners such as lawyers may be willing to to help a writer with a project. Just be discrete, never waste their time, and don't become a pest.

 

Writing about your own knowledge and experience is most likely your best bet. With effort and thought, however, you can find reliable sources that open doors for strong stories which ring true because they are based on fact, not fantasy.