A serial killer named The Shark is terrorizing London by killing his victims with a speargun and then, dressed in a scruba-diver's wetsuit, escapes using the city's sewer tunnels. Inspector Wade of Scotland Yard (Joachim Fuchsberger) is assigned to the case and he suspects that the Shark is tied in with a smuggling ring the authorities believe is run out of a dive on the Thames waterfront called The Mekka. Also stars Brigitte Grothum and Elisabeth Flickenschildt. Also with Klaus Kinski. (In widescreen format).