TUNG and PUI are deeply saddened by the death of YIU although they believe that this is somewhat a way out for POK. Madam YUK, who looked after YIU in the hospital when she was still alive, gets poisoned and falls unconscious after taking a bite of the cake given by YIU. SUM is shocked to find some cantharidin (a poisonous chemical compound used in Traditional Chinese Medicine) in the cake. Laboratory test results show that YIU was poisoned continuously for a certain period of time, which makes SUM believe that POK may have something to do with YIU’s death. YAU suspects that POK and PUI have rekindled their relationship. She becomes even more suspicious when she spots PUI burning the letter from POK. Given all the circumstantial evidence, she decides to hold POK and PUI for questioning. TING believes that POK and PUI are innocent. To prove PUI’s innocence, POK needs TING to find out where her sister has gone over these days.… ...