Conversation so far:
What is the rating of the movie Tropic Thunder?
Tropic Thunder is rated R.
Who are the actors in the movie Tropic Thunder?
Ben Stiller, Jack Black, and Robert Downey Jr. are the actors in Tropic Thunder.
When was the release of the movie Tropic Thunder?
Tropic Thunder was released on August 13, 2008.

Question: Who produced the film?
Self-contained rewrite: Who produced Tropic Thunder?