The film will take place in the 1930s on the MGM lot and will apparently feature cameos from people like Judy Garland and Bugsy Siegel (people playing them, anyway). The plot will likely follow the detective as he is hired by the studio to clean up a scandal involving a starlet who may or may not have murdered her husband. The only other part of the script that has been revealed is that there will be a major shootout that takes place in the Trocadero nightclub on Sunset Boulevard. Despite the fact that no studio is yet confirmed (New Line has been revealed to have bid, but too low), the film will start shooting in February.
There can never be too many period noirs set in Hollywood, which had a lot of interesting scandals during the golden era, but after the failure of The Black Dahlia some studios may be hesitant to think there's a chance for another L.A. Confidential. Still, with Mann, DiCaprio and Logan teamed up -- they all worked together on The Aviator, which Mann produced -- it will be difficult to lose with this film.