The story-telling is complex, with lots of flashbacks.
As director Sergio Sollima says in his comments, there is everything here that any action movie fan could ask for, and MORE. His words. The more is the depth of characters and great use of American locations. Score by Morricone. It's well-known in noir lists by critics.
Bronson plays a professional hitman whose life goes into crisis. It has echoes of "Out of the Past", because of the triangle that arises with Jill Ireland between him and gangster boss Telly Savelas. Telly doesn't frame Bronson, but he uses him through femme fatale Ireland. She projects vulnerability and weakness while plotting with Telly's lawyer to become #1 in his nearly legit business empire. Michel Constantin has a small part as a close buddy of Bronson who got him started as an assassin. The dubbing, I think, of Constantin is lip-synched amazingly well.
The story is a tragedy. Sollima worked on it with Lina Wertmuller. Love and bullets do not mix, that's one theme. Bronson did a movie of that title in 1979.
The movie opens with an auto chase sequence set in St. Thomas, where my wife and I honeymooned. How could I not recommend this film? And later it explores New Orleans locations to boot.
Bronson movies are holding up well. Any of the Death Wish series looks good, and they look good in comparison to the recent Bruce Willis version, which itself is a credible remake, with a tone of respect to the original. The remake is toned down, almost as if they were fearful of giving it an edginess of the original, a fear of failing to live up to the original.