诸国纷争群雄争霸的两千多年前，赵国为一举攻下势均力敌的燕国，决定先拿夹在赵燕之间的梁国开刀，于是妇孺平民加起只有四千余人的梁城被赵国十万大军包围。危难之时，梁王（王志文）向以守城著称的墨家请求一支可以抵抗赵军的守军，却等来其貌不扬孤身应战主张“兼爱非攻”的墨者革离（刘德 华）。 　　革离出奇制胜，令赵军无功而返，后为应付赵军随时而来的庞大攻击，又亲自练兵制造无数特别兵器，梁城上下对其无不折服，更得到逸悦将军（范冰冰）的爱慕，然而，杀气也在此时降临他的四周。In 370 B.C, China was separated as seven nations and several other small tribes, one of these being the city state of Liang. The nation of Zhao is led by the terrifying prime commander Xiang Yangzhong who orders his troops to launch an attack on Liang in a bid to conquer the small city. Leaping to the defense of the cowed people of Liang is a warrior who goes by the name of 'Ge Li' from the Mo-Tsu school of thought, renowned for its defensive skills, respect for simplicity and peace, and belief in universal love. He is their last hope as the terrors of Yangzhong's troops are unleashed. The future of Liang now hangs in the balance, with all their hopes pinned on the mysterious Mo-Tsu warrior Ge Li...