In this TV series, Terence Hill could be heard in his own Italian tongue for the first time in his career. In all his previous film and television appearances, he had been dubbed by someone else, even in his home country.
Singer and songwriter Pino Donaggio, who reached worldwide success in 1965 singing Io che non vivo senza te - that was later recorded by Dusty Springfield and by Elvis Presley with the title you don't have to say you love me - is the composer of Don Matteo's main theme.
In first season's Il fuoco della passione actress Milena Miconi appears as the lover of the adulterous husband. Four years later she would appear as Gubbio's major Laura Respighi during two seasons.
In first season's Delitto accademico a poster of Calimero can be seen in the medical college announcing Gubbio's aquiloni festival.
In second season's Scherzare col fuoco appears actress Sydne Rome, who was linked to singer Julio Iglesias and later married to pope's doctor. She will also appear five years later in the series in a very different role.