Lady in Black Cracks the Gate of Hell (1967)

Ghost-faced To is murdered in a mortuary after paying a visit to Muk Lan-fa. A set of teeth is found missing from another dead body. Lan-fa’s sister Sau-chen follows the leads on a business card To left behind to a dental clinic which suddenly bursts into flame. The news of her sister’s abduction by the infamous Japanese criminal Katsu Saburo soon reaches Lan-fa. Working together with her police friend Ko Cheung to crack the case, Lan-fa analyses photo evidences in minute detail. The duo order the retrieval of a pole that has survived the explosion intact while lying in wait at the clinic. Sau-chen, who has escaped, saves the duo from the chiller where they are detained. Inspector Yeung retrieves the operation plan concealed in the pole and the secret codes in the set of teeth, but the spook is shot dead by Katsu before he could reach the Hell’s Gate and the treasure buried there. Constable Kwan, and others and wipes out the gang at the Hell’s Gate.