The Girl in Via Condotti is a film noir set as a giallo with crime, detective and mystery elements. Sandro (Frederick Stafford, Topaz) is a private investigator in Rome, whom French wife Simone (Patty Shepard, Mio caro assassino) has fallen in alcoholism and debauchery. One evening she is strangled by one of her lovers, a mysterious unknown. As usual the police, led by the commissioner Palma (Michel Constantin, Citta violenta) with the support of the procurator (Arturo Dominici, Indagine su un cittadino), remains in the dark, but Sandro, helped by his friend Tiffany (Claude Jade, Number One), a photographer, decides to lead his own inquiry. They blow up a photography of a helmeted biker found near Simone's body and recognize in the background Laura (Femi Benussi, Omicidio per vocazione), a stripper artist. When they meet, Sandro and Laura fall in love, but Laura is the mistress of an powerful lawyer, Giorgio (Alberto de Mendoza, Una sull'Altra).
As Sandro goes on with his investigation, he meets the traditional characters of the underworld: the prostitute Gina (Dada Gallotti, Il Coltello di ghiaccio), her pimp Franco (Manuel de Blas, Las Trompetas del apocalipsis), the witnessing taxi driver (Pupo De Luca, La Controfigura), the blackmailer Mario (Simon Andreu, Passa di danza su una lama di rasoio), who happens to be Laura's brother, the informer Broccole (Giuseppe Castellano, Gli Assassini sono nostri ospiti), and a dangerous sniper (Antonio Basile, Perche quelle strane gocce di sangue sul corpo di Jennifer). Will Sandro and Laura be able to start a new life while sharing their love? Corpses go on piling up as Sandro gets nearer the truth. (Viewed in Italian 1h33 version.)
