定安是炼封号铸刀厂的继承人也是师傅钦定的接班人，后来在师傅的口中得知自己的父亲乃是被马贼飞龙所杀，而铸刀场的大殿之中所供奉的那片断刀，便是定安父亲的遗物，得知真相的定安，决定带走断刀为父报仇，师傅的女儿向灵为了追随定安，却被马贼掳走，定安为了能够救回自己心爱的女人不幸遭飞龙的暗算，被斩落一臂坠落山崖。手臂被断的定安，感觉复仇无望便退出江湖不料，人生再次出现转折，在意外之中定安得到了半本绝世刀谱，于是再次下定决心，重新拿起锻刀为父报仇，因无法握刀，他便自己根据绝世刀谱，独创了断臂刀法，经过苦心修炼之后，他便带着断刀前往马贼的营地复仇。最终在自己的断臂刀法之下斩掉了飞龙救下了炼锋号铸到场

Ding'an is the heir of the Lianfeng Knife Foundry and the successor appointed by the master. Later, he learned from the master that his father was a horse thief and a flying dragon. The piece of knife that was enshrined in the main hall of the knife casting field was the relic of Ding'an's father. After learning the truth, Ding'an decided to take away the broken knife to avenge his father. In order to follow Ding'an, Xiang Ling, the master's daughter, Taken away by horse thieves, Ding'an was plotted by Feilong in order to save his beloved woman, and fell off a cliff with one arm cut off. Ding'an, whose arm was broken, felt that revenge was hopeless, so he withdrew from the arena. Unexpectedly, his life turned again. In the accident, Ding'an got half of the peerless sword manual, so he made up his mind again and picked up the forging knife again to avenge his father, because he could not hold the knife. , he himself created the Broken Arm Saber Technique based on the peerless sword manual. After painstaking practice, he took the Broken Saber to the horse thief's camp for revenge. In the end, he cut off Feilong and rescued Lianfeng Haozhu with his Broken Arm Saber Technique