When Ryuji - the Gun Slinger, a drug addict leaves hospital to which he was taken after a gunfight by a notorious killer named Gin of Colt, he is employed as a bodyguard by Yo Sangen, chief of a narcotics smuggling ring.

暗黒街を舞台に“決して相手を殺さず、利き腕を打ち砕く”抜き射ちの名手・竜二（赤木圭一郎）。彼は偶然見かけた、弟分で麻薬中毒の元ボクサーを救け出すために、同業者“コルトの銀”と死闘を繰り広げることになるが・・・。日活第三の男、赤木圭一郎の”拳銃無頼帖”シリーズの記念すべき第一作。