He finished school before his seventeenth birthday with the highest marks and enrolled at Sapienza University of Rome, where he studied chemistry.

[7] Pedersoli returned to Italy in 1949, and played water polo in Rome for Società Sportiva Lazio Nuoto and won the Italian swimming championships in freestyle and mixed relay teams.

As a professional swimmer in his youth, Spencer was the first Italian to swim the 100 m freestyle in less than one minute when on 19 September 1950 he swam the distance in 59.5 s in Salsomaggiore.

[8] In 1949 he made his international debut and a year later he was called up for the European championships in Vienna where he swam in two finals, finishing fifth in the 100 m and fourth in the relay 4 × 200 m.[9] In the 1951 Mediterranean Games in Alexandria (Egypt), he won a silver medal in the same 100 m freestyle event.

[10][11] Pedersoli participated in the 1952 Summer Olympics in Helsinki, Finland, reaching the semi-finals in the 100 m freestyle (58.8 s heats, 58.9 s semi final).

[16] Pedersoli's first film role was in Quel fantasma di mio marito, an Italian comedy short released in 1950.

[17] In 1951 he played a member of the Praetorian Guard in Quo Vadis, an epic film shot in Italy made by MGM and directed by Mervyn LeRoy.

[17] During the 1950s and early 1960s, Spencer appeared playing minor parts in Italian including Mario Monicelli's movie A Hero of Our Times, with Alberto Sordi and the 1954 war film Human Torpedoes with Raf Vallone.

[18] He signed a contract with RCA Records to write lyrics for singers such as Ornella Vanoni and Nico Fidenco and soundtracks.

While Hill's characters were agile and youthful, Spencer always played the "phlegmatic, grumpy strong-arm man with a blessed, naive child's laughter and a golden heart".

In the Italian versions of his films, Spencer was generally dubbed by actor Glauco Onorato due to his thick Naples accent,[25] although he was voiced by Sergio Fiorentini in Troublemakers, To the Limit (1997) and the Extralarge series (1991–93).

[34] Spencer's grandson, Carlo Pedersoli Jr., is a mixed martial arts fighter currently signed to the Ultimate Fighting Championship.

[41] The statue's pedestal bears the inscription Mi sohasem veszekedtünk ("We never fought"), a quote from Terence Hill's eulogy referring to their long-lasting friend- and partnership.