Is it okay to write a sequel to a series of movies already produced?

To clarify, I want to write an Amityville sequel. I figured if adaptations of books were okay, then this would be, too. But I want to be absolutely sure before I proceed.

It's something I only intend to use as a future writing sample, not as something to sell. I know you can't do that.

Thanks in advance.

Jaymie

I believe this would be fine... it's kind of like a fan fiction thing, in my mind. You're allowed to write it, for sure, but as you said -- anything beyond that is not likely going to fly.

why not? I'm writing the sequel to my last year's Script Frenzy. It's a trilogy.

Thank you. Now I can get back to work!