Many years ago, because of schizophrenia, Yeung Bik-sum almost poisons her son Ip King-fung and her daughter Ip Long-ching. King-fung experiences seismic change and develops a split personality that manifests as intelligent weakling Chu Kei, a diligent student who eventually qualified as a graphologist. A double bomb case and another blood writing naked corpse case prompt CIP Kong Ching-fun to assemble a task force to pursue the perpetrators. The task force members are King-fung, psychiatrist Wai Yui-kit, bomb disposal officer Yau Ngan-sing and forensic anthropologist Fong Yuen-chin. Father of criminal investigation Nip Shan recovers from bipolar disorder. He is assigned the task of overseeing the task force investigating all kinds of bewildering cases. He finds out Bik-sum seems to be implicated in the mystery of his wife Leung Yat-sze’s disappearance. While the maze is being unraveled piece by piece, how do the chums face up to the crunch?