Drama follows an American journalist (to be played by Clooney) drawn into a murder mystery in post-war Berlin, where he's searching for his wartime mistress (Blanchett). Paul Attanasio wrote the script.
Maguire will play a seemingly innocent soldier who drives the journo around town and has motives of his own.
The Good German will be shot in black-and-white on WB's soundstages. Production begins in the fall.