Gianna Lou Cassini (née Müller; born January 2, 1949), better known with her stage name Nadia Cassini, is a retired American actress, singer and showgirl who became famous in Italian exploitation films of the 1970s and early 1980s, particularly in the commedia sexy all'italiana genre in late 1970s.

She had roles in films such as Pulp (1972), Ecco lingua d'argento (Emmanuelle's Silver Tongue) (1976) and Starcrash (1978) before reaching a great success in the commedia sexy all'italiana genre (a series of films starring Lino Banfi between 1979 and 1980), namely L'insegnante balla... con tutta la classe (1979), L'infermiera nella corsia dei militari (1979) and La dottoressa ci sta col colonnello (1980).

[2][3] In the 1980s, after appearing as a showgirl in some successful TV shows such as Drive In and Premiatissima, her face was partially disfigured and her right ear lost in a botched plastic surgery procedure.

[2][4] After retiring from the Italian scene, Cassini worked for French television and later returned to the United States.

She divorced Cassini in 1972 and moved to London with her boyfriend, Greek actor Yorgo Voyagis.