How to write a complex query with doctrine?

When is the best time to write Screenplay: Before or After Query letter?

• I have been seeing different answers for this. One website said to write script after you recieve interests in your script. However, another one said the have a polished script before you even send in your query letter. I believe I should persure the second advice (because it makes more sense.) What is your advice?

• Answer:

  I'd write it beforehand. You'll need a lot of time editing and polishing and getting beta readers for your script, and I"m not sure an agent will want to wait that long... They might move on to other promising prospects or by the time you get around to writing and polishing and getting feedback and rewriting/revising, they might have forgotten all about you and even worse, they might have taken on a client who's written something similar to yours and are no longer interested in what you have to offer.