screenplay

five years ago I recieved a copyright on a screenplay
that I wrote. I live in Illinois and have sent this screenplay to several blind ads in the trades(L.A.)
I now realise my mistake. There is a television show
that is so similar to my work, it could not possibly be
a coincidence. Even the name of the protagonist .
This particular script has placed in a few compititions,
so anyone could have read it.

What can I do?

Contact an attorney and if there is a colorable claim the attorney will make a demand.