2,500 years ago Persia was a great empire; regarded as the forerunner of the Roman Empire. However in spite of its size & strength it had an adversary that would seal its doom. Persia's nemesis was a smaller empire - Macedon; ruled by Alexander The Great. Did the Persian Empire fall because it was a colossus built on shaky foundations? For centuries the Persian Empire had existed in what appeared to be resolute stability--until collapsing in a relatively short period of time under the military strikes of Alexander the Great. How was this possible? Greek historians claim that it was the moral decline of a whole society. In our high-tech electronic "war room", experts simulating the battles of Issos and Gaugamela make startling new assessments of the military performance of the Persians--and of their last king, Dareios lll.