Anna Tredicesimo, wife of Luigi Tredicesimo of Santa Ninfa (Trapani), introduces herself to the private investigator Lionel Lionelli and instructs him to recover some red briefs, purchased by her jealous husband in Paris, and lost by her during a loving meeting with the heartthrob fetishist Gianni Agazzi. Lionel, recommended by his friend ten. Sheridan, begins the research and chases the panties from Agazzi to Lola Lola Bis, a stripper, and from this to Iolanda, Ennio's girlfriend, member of Hell's Angels. Lionelli, a bungler by nature, finds the path difficult and also dangerous because, as he will learn very late, a microfilm with a secret chemical formula is hidden in the briefs and, consequently, his steps are constantly followed by men of the boss Goran , master of Titan.
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