The war in Iraq, seen nightly on tv sets around the world, has finally made it to a theater near you. Four docs about the ongoing conflict are hitting theaters this winter and more are sure to follow. Few, if any, will have the power of BattleGround: 21 Days on Empire's Edge. Having cut his teeth on innumerable music videos and short political pieces for his website Guerrilla News Network, Stephen Marshall ups the ante in his first feature-length documentary. Following soldiers, Iraqis citizens and some interested outsiders, Marshall maintains the visual flair that marks much of his work, but keeps it firmly in service to his story. What could have been a simple polemic develops into something much richer, as the interests and actions of these men plumb the intricacies, good and bad, of the US occupation. 82 min.