One of the major locations in The Dark Knight Rises, please recall, was the prison fort where three of the characters in the story were held: Mehrangarh Fort. The fort appears to have direct links to the Sikhs. The fort is one of the largest in the world.
According to IMDb, here are the Sikh personnel working on The Dark Knight Rises, for the Second Unit, India ~
Krishan Pratap Singh, assistant director: India (who is also involved with Zero Dark Thirty, to be released on 19 December 2012, USA, about Navy SEAL Team 6 tracking down wanted terrorist Osama bin Laden),
Vans Pradeep Singh Rathore, location manager: India,
Chandradeep Singh Rathore, director's assistant: India, and
Dileep Singh Rathore, line producer: India.
For more on the August 5, 2012, Oak Creek, Wisconsin shooting at a Sikh Temple, which left seven dead, please see here.
In the first film of the Dark Knight trilogy, in Batman Begins, there is a scene with Katie Holmes in the foreground, in which a random Sikh shows up in the background. This has been the source of some comment by Sikhs, before today. See here.