Correct!

All you need to have is a title, a log-line and a synopsis. If you want to read further on the requirements, please read:
What is the difference between a log line and a synopsis?
Sample Movie and TV show form.

Question: Can an idea for a movie or TV show be copyrighted?

Answer:

1. Yes, an idea can be copyrighted and 100% secured.
2. No, an idea cannot be copyrighted and cannot be secured.
3. No, an idea cannot be copyrighted but can be secured.