Conversation so far:
When was the premiere of the film, Dreamgirls?
Dreamgirls premiered on December 4, 2006.
Where was the premiere of the film, Dreamgirls?
The premiere was at the Ziegfeld Theatre in New York City.

Question: When was the official release of the movie?
Self-contained rewrite: When was the official release of the film, Dreamgirls?