Violent City (1973) on Netflix

After being double-crossed by his mistress and barely escaping a murder attempt, a hit-man sets out to take his revenge on the woman and the mob boss who put her up to it.

After a bloody double-cross leaves him for dead, professional hit man Jeff tracks the shooter and his beautiful mistress to New Orleans. But when Jeff takes both revenge and the woman, he finds himself blackmailed by a powerful crime boss who wants the fiercely independent gunman to join his organization. Jeff refuses, and is hunted through an unforgiving city where love is like a loaded gun and debts of vengeance are paid in bullets.

—Edwin van Oorschot <info@edwinvanoorschot.nl>