“The Cop in Blue Jeans,” appearing in 1976, is a thriller about a solitary police officer that recalls films like “Dirty Harry” (1971) and “Serpico” (1973). The main character bears a resemblance to Serpico himself. However, this one comes from Italy, directed by and co-written with Bruno Corbucci. It centers on an undercover operative named Nico Giraldi (Tomas Milian), who makes several arrests of thieves and focuse…