Francesco 'Nino' Castelnuovo was born to humble beginnings in Lombardy, the second of four brothers. His working life began with a series of stints in various jobs, including house painting, as a mechanic and as a sales agent, after which he decided to take drama classes at the Piccolo Teatro in Milan. A first screen appearance in 1957 was followed by a motion picture debut two years later. He had a small supporting part in Luchino Visconti's Rocco e i suoi fratelli (1960), but his career only gained traction with a co-starring role opposite Catherine Deneuve in the romantic musical drama Les parapluies de Cherbourg (1964) (though his scenes were subsequently re-dubbed). Castelnuovo's greatest popularity came via the small screen, as Renzo Tramaglino, key protagonist of the mini-series I promessi sposi (1967), a period piece set during the Spanish occupation of Lombardy in the 17th century and based on a best-selling novel by Alessandro Manzoni. Other appearances have included both American and Italian-produced westerns (The Reward (1965), Un esercito di 5 uomini (1969)) among notably cosmopolitan casts. By the early 70s, Castelnuovo acted primarily on stage, in serial television and was seen for several years in commercials for Olio Cuore, a corn oil company. His final fling on the international scene was a small role in [The English Patient (1996)] as an archaeologist, recalled in flashback scenes by the lead character Almásy. Castelnuovo retired in 2016. He was married to the actress Danila Trebbi.