The Sicilian Clan offers splendid performances by Jean Gabin and Alain Delon, plus an exciting (if somewhat far-fetched) denouement. I also very much liked Killing Zoe, a Franco/American production with an awe-inspiring performance by Jean-Huges Anglade and solid work by Julie Delpy and Eric Stolz--something like Dog Day Afternoon without the mordant humor.
A truly brilliant Italian Mafia film: Mafioso, directed by Alberto Lattuada and starring the great Alberto Sordi--only the Italians can bring off tragedy, pathos and humor with such panache.