前作中以三号机驾驶员巴武藏的牺牲为代价,终于打败了恐龙帝国,但又出现了由有角人类构成的百鬼帝国也要征服世界。补充了新驾驶员車弁慶及新机器盖塔G的早乙女研究所又投入了战斗。。In 1943, revolutionary inventor Nikola Tesla died penniless in the New Yorker Hotel. Within 24 hours the U.S. government seized everything in his room. But one design was already missing. Seventy years later in Buffalo, NY, a brilliant young engineer has found it. And the only person she can trust is a low-rent detective with a pack-a-day habit.。在一貧窮村落,有一位口才了得的狀師戴亞斗(鄭丹瑞)。村民每有任何冤情申訴,均禮聘他作其狀師, 斗因而聲名大噪。斗家乃狀師世家,種下不少冤孽,其母恐斗絕後,遂為他娶–童養媳梅群娥(崔加寶)。然而,斗卻對縣官商君綿(黃新)之女商湘(蔡少芬)情有獨鍾。 後綿之親戚因貪污而被抄家,綿亦被牽連其中。斗與湘赴京營救綿,欲請著名狀師卓一言(曾偉權)相助,卻被拒於門外。幾經波折,斗終為綿洗脫罪名,並獲慈禧太后御賜金牙,成為金牙大狀。 不久,斗認識名妓伊靜(鍾淑慧),靜對斗生愛意,惜斗不為所動。及後,靜離奇被殺,斗亦被捲入案中。追查之下,斗發現真兇竟是好友倪鐵樑(林嘉華)。究竟斗能否為自己洗脫罪名?真兇又會否被繩之於法?。