Apple has unleashed a new promo for Tropic Thunder, a mockumentary called "Rain of Madness" which explores what happened during the shooting of the movie within the movie. German born documentarian, Jan J&#252rgen blows the lid off Hollywood, exposing the frenzy, the insanity and the madness surrounding the filming of "Tropic Thunder". One of the most ambitious war films ever made.

The Ben Stiller-directed action-comedy hits theaters August 15th, and stars Stiller, Jack Black, Robert Downey Jr., Nick Nolte, Brandon Jackson, Steve Coogan, Danny McBride, Bill Hader, Jay Baruchel, Matt Levin, Andrea De Oliveira and Reggie Lee.

RELATED: Does Robert Downey Jr. Think Tropic Thunder Could Get Made Today?

Also, the official website for "Rain of Madness" can be accessed here.