Lera is a sociology student at a small-town university. Her mother is a sleepwalker who believes in miracles, and her father just left the family for another woman. Lera has no idea how to make her life better. And one more thing: a spirit keeps visiting her dreams at night. And the harder Lera's life gets, the more often she has these dreams. That is, until the spirit steps in...

亚瑟（克里夫·欧文 Clive Owen 饰）与家人在战乱中失散，被人收养担任杂役工，但魔法师却预言他会成为神圣的英国君主，而亚瑟更是拔出了“石中剑”印证了自己的将来。当他看到国家的混乱现状，发誓要让整个大不列颠群岛脱离罗马人的残暴统治。于是他下定决心要建立一个全新的，充满和平宁静气氛的家园。亚瑟的骁勇善战和超凡的气魄令一些非常优秀的骑士为之折服，纷纷加入他的队伍，组织成著名的“圆桌骑士”。这些英勇的战士在亚瑟的带领下一路势如破竹，取得了令人骄傲的战绩。