Whether Prizzi's Honor has been intended as a subtle parody is beyond the author's ability to know but let's look at it like that because it is the only sensible way to look at this movie if you don't want to call it a failure. Prizzi's Honor is a film with good acting for the most part and it is coming from a very renowned director what John Huston is. Yet, the movie lacks an overall sense of believability and it does not convince us it tells a story that could actually happen. Because of that it is better to consider the film a parody.
Prizzi's Honor is about Charley Partanna (Jack Nicholson), a professional hit-man working for the Prizzis, one of the biggest and richest East Coast mafia families. He falls in love with Irene Walker (Kathleen Turner) which is a hit-woman but this is a fact still unknown to our hero. It appears that Irene has worked with the Prizzis as a free-lancer. In addition, it seems that Irene might have been involved in some affairs not welcomed by the Prizzis. Naturally, problems appear. To make them worse, some unpleasant events accidentally happen which complicate matters more. But the worst is yet to come as both of them receive some painful to fulfil orders by the family godfather Don Corrado Prizzi (William Hickey) and his son while the Don's granddaughter Maerose Prizzi (Anjelica Huston), a former Charley's lover, does not hesitate to make everything even trickier for the couple.
Having Jack Nicholson, Anjelica Huston and Kathleen Turner in Prizzi's Honor's cast presupposes strong acting. And in fact, acting is the most acceptable side of the movie. Nicholson and Turner are not convincing as professional killers but it is mainly due to screenplay issue and not because of their skills. Anjelica Huston does not have a lot of screen time but it seems it has been enough to grant her an Academy Award for Best Supporting Actress. The film has garnered 7 more Oscar nominations but some of them are disputable, especially the ones for Best Picture, Best Director and Best Writing.
Prizzi's Honor begins and ends very improbable. A man falls in love and is convinced he has found the love of his life in just a few minutes. A woman cheats one of the most powerful mafia families in the country, yet she does not try to hide and even puts herself in the family's paws. Concerning the screenplay further, let's skip some of the ending's boners in order not to spoil the movie anymore. And as far as the directing adds to the film's lack of any clear vision and good storytelling details, Prizzi's Honor is definitely not among the best directed John Huston's motion pictures which is a pity since Huston has undeniably created some very enjoyable and important movies in the history of cinema.
One distinctive feature of Prizzi's Honor could be that it gains some momentum in the middle of the narrative and this does not happen so often. Usually, if a film is uneven, it is good at the beginning or during its second half but rarely sparks just in the middle. And it is exactly the case with Prizzi's Honor. Yet, this alone is not anything that could improve the movie experience considerably.
To be objective, the film possesses some charm if we consider it a parody. There are funny moments and there are some characteristics of a parody. But it is really a subtle parody. And for some reason, usually, subtle parodies do not work very well. If it's an obvious and even rude mock as Mel Brooks' ones, you either love it or hate it. But when it is a concealed skit, it most often loses its strength. Not that it's impossible a good subtle parody to be created but it is not the most common thing to happen.
You can still see Prizzi's Honor and find it enjoyable. At least Jack Nicholson stars in the film and he is someone that often could save a movie cause Nicholson is indisputably one of the greatest actors ever. But if you are in the mob films you better try something else, e.g., A Bronx Tale.