structural:expansion
1970s

In the early 1970s, Delon made another attempt at the English-speaking market. The Assassination of Trotsky (1972) for Joseph Losey was poorly received, but Red Sun (1972), with Charles Bronson and Toshiro Mifune, did well. In France he appeared opposite Simone Signoret in The Widow Couderc (1971). He starred in his third film with Melville, Un flic in 1972 as well. He then produced and starred in a romantic drama, Indian Summer (1972), and subsequently appeared in the thrillers, Traitement de choc (1973), and Tony Arzenta (1973).

In 1973, he recorded a duet with Dalida, " Paroles, paroles ", that went on to become one of the most recognizable French songs. He tried again for Hollywood stardom with Scorpio (1973), with Burt Lancaster for director Michael Winner. It was only a minor hit. In France, he made The Burned Barns (1973) and Creezy (1974). He produced Two Men in Town (1974) which re-teamed him with Jean Gabin, and Borsalino & Co. (1974), a sequel to his earlier hit.

After another gangster thriller, Icy Breasts (1974), Delon returned to his first swashbuckler since The Black Tulip, playing the title character in the 1975 Italian-French film Zorro. He made some more crime filmes: The Gypsy (1975), Flic Story (1975) (with Jean Louis Triginant), Boomerang (1976) and Armaguedon (1976). In 1976, Delon starred in Monsieur Klein, for which he was nominated for the César Award.

It was back to crime for another series of thrillers in which he starred as well as produced: Man in a Hurry (1977), Death of a Corrupt Man (1977), Le Gang (1977), and Attention, The Kids Are Watching (1978). In 1979, Delon stated that only a quarter of his business activities involved films, that he also had "a helicopter business, built furniture, promoted prize fights, and raced horses", and that he was still interested in becoming a star in America.

In 1979 he made a final attempt at Hollywood stardom, signing with agent Sue Mengers and starring in The Concorde... Airport '79 (1979). The film was not a big success. Delon returned to acting in French films, playing in and producing The Medic (1979) and Three Men to Kill (1980).