Accompanied by the Venice police Smith, Petrie and Kerrigan search the Palazzo Brioni and are led to an underground pool by Rudolph Adlam's screen. They arrive in to time to see him killed by piranha, a species of man-eating fish. Searching the palazzo for Fu Manchu Smith suspects that the insidious doctor may have left Venice on Brownlow Wilton's yacht, Silver Heels. Dispatching Kerrigan to Paris to follow a clue in that direction, Smith in the company of Petrie and Lazio follow the yacht. When questioned Wilton admits that he'd received notes from the seafan (?).  He offers Smith and Petrie a drink and shortly after Smith reels and falls to the floor...