Heung Yat Jeen was saved by a kind-hearted man when he was young and since then, his life ambition was to become the world’s best detective. His training and hard work paid off when he solved a mystery case on his first day of work. However, his superior, Ching Ying Hung, was envious of Yat Jeen’s glory and purposely sent him on a dangerous mission to capture a mass murderer, Yi TeenBong.