The vice-president of Lloyd’s International, Winterbottom, knowing that the Sicilian mafia has been able to insure some drug shipments, calls Jack Clementi to solve the case. Clementi starts his research in Rome using some information from captain Caruso, an old friend who works for the Criminalpol.

Jack Clementi, reading the newspaper, learns that there is an imitation of the precious Etruscan goldsmith’s masterpiece ‘The laughing girl’. The article says that the piece belongs to the Houston Museum to which the deceased Texan billionaire and collector Jim Carlson donated it. But Jack knows that the precious statuette belongs to the feudal lords of Roccaferro who have kept it for two hundred years in the castles museum, with an insurance guaranty from Lloyd’s for 800,000 sterling pounds.

Big Man is hired by the manager of Sfnix, a leader business on technological armaments, to track down the criminals who stole the prototype of the the U.S.R., a new radiation beam rifle. The thieves were not able to steal the lethal weapon's computerized tracking system and are now threatening Sfinix with a massacre in order to get it. Feeling that the theft had been planed with the complicity of an employee of the Sfinix, Big Man, together with his good assistant Simon, investigates.