Serenity premiered in France at the 31st Deauville Festival of American Film on September 3, 2005, in Deauville, Normandy.
The Deauville Festival of American Film is a European showcase for mainly American movies; this is a very popular film festival in France (second only to Cannes!). It is a launching pad for both independent and studio movies in Europe. This is the festival where you can run into Spielberg and Kevin Smith on the same day!
Here are HQ pictures of Summer Glau and Nathan Fillion during a photo call for the presentation of Serenity.