One day, the high-ranking Assistant Commissioner of Police Josephine (Maggie Siu) suddenly appears at the Western District Police Station to personally review a trivial case of child abuse. An eleven-year-old girl was beaten to death by her biological mother, Bik Chi (Natalie Tong). Bik Chi has already admitted to killing her daughter, and her cohabiting boyfriend (Eric Pang) has also been charged in connection with the death of his younger daughter (Ziqing Luo). A deranged Josephine relentlessly pursues the truth, and one cruel interrogation after another is vividly brought to life on screen through torture and coercion.