A serial killer is hunting New York City. Grizzled veteran police detective Edward Delaney (Frank Sinatra) is investigating the case. His wife Barbara (Faye Dunaway) is in the hospital. He enlists the help of ancient arms expert Christopher Langley.

Sinatra is playing a tired cop who is distracted by his wife's illness. It does not make for a compelling investigation although it may be more accurate. It's a darker reserved performance. The more exciting character is eager Langley searching for the murder weapon in the local shops. He has a couple of hilarious scenes. Otherwise, this is grinding film about the grind of a grinding investigation. While I appreciate the personal aspect of the wife, it doesn't make it compelling as far as the investigation goes. Although it does not excuse the horrible insult of someone nominating Dunaway as the worst actress. The woman is in bed dying for most of the movie and that's what she gives. This is a bit of a grind to watch but it somehow maintains my attention for the most part.

A serial killer is stalking New York, Edward X. Delaney (Frank Sinatra) is a NYPD Inspector who is assigned the mission to investigate , as he is tracking down an apparently motiveless killer . Meantime, he is worrying about his spouse (Faye Dunaway) becoming increasingly unhealthy after a kidney operation was wrong . Delaney has to investigate if the victims somehow linked and what does the brutal method of death signify. He's searching for a killer. She's searching for a miracle .... And time is running out.

Thriller and exciting movie with a skill intrigue , suspense , chases , grisly killings and religious imagery . However , failing to convince due to dull and tiring scenes about the sad illness of the unfortunate wife . Concerning a simple and ordinary plot about a police inspector , nearing retirement , tracks a serial killer who is terrorizing New York . Frank Sinatra gives a nice acting as a detective who is attempting to put together the pieces of a confused case in spite of his impeding retirement and wife's sickness . Based on the bestseller novel written by Lawrence Sanders' that seems to be a lot more interesting than this picture . The picture is acceptable though the plot about the ill wife results to be entirely superflous and boring . As the relationship between the Police Inspector/Frank Sinatra and his wife/Faye Dunaway haunts the script and seems to have been inserted totally for sentimental reasons . Starring duo are accompanied by a very good support cast such as : David Dukes , George Coe , Brenda Vaccaro , Anthony Zerbe , James Whitmore , Martin Gabel , Victor Arnold , Eddie Jones , Jeffrey DeMunn and Joe Spinell.

It packs an adequate musical score by Gordon Jenkins with plenty of intrigue and suspense . As well as atmospheric and appropriate cinematography by Jack Priestley . The film was well handled and professionally directed by Brian G. Hutton ; however , being a flop and failed to give cash . Hutton started his career with little and prestigious films , such as ¨Wild seed¨ and ¨The Pad¨. There after , he veered off into big budgeted and all-star movies, proving which he could handle big scale production , as ¨Where the eagles dare¨, one of the best from Alistair McLean , furthermore with ¨Kelly's heroes¨ added humor to the warlike action . His next picture was ¨High road to China¨ marked a partial return with panache to his previous form . This ¨The first deadly sin¨ faltered at the Box-office , in spite of being an entertaining thriller well starred by Frank Sinatra and with occasional touch of directorial skill , that's why is a must for Sinatra fans .

I saw someone else's user comments on this film and I can't believe that there were going to be series of films based on Frank Sinatra's character mainly because of the ending this film had. If you're thinking that gives the ending away, don't look for an obvious conclusion.

To his credit, I guess Frank Sinatra did not want to end his film career with Dirty Dingus Magee. He wanted to end his film with the serious part, unfortunately The First Deadly Sin messes up the telling of a potentially good tale.

Frank Sinatra is days away from his retirement as a Detective Sergeant and a strange murder has been assigned to him. A man apparently selected at random is killed with an unidentified weapon that is just driven into the top of his skull. A little good detective work and he finds their just might be a pattern of killings.

It's all in identifying the weapon and it's an unusual one at that which I won't reveal. A professor in medieval history played by Martin Gabel helps with the hunt and later on he's joined by the widow of Sinatra's victim, Brenda Vaccaro to help with the hunt.

They're helping because Sinatra's new captain is one total jerk played by Anthony Zerbe. Maybe I'm missing something in Zerbe's performance, but I would think that an ambitious guy like Zerbe plays would instead of pooh-poohing Sinatra's ideas would think that this guy if he is on to something with this serial killer business. And if he's right Zerbe will get all kinds of accolades for figuring this out in his precinct and even more if the doer is apprehended. It's an absolutely impossible role and poor Anthony Zerbe can't do much with it.

All this while Frank's wife Faye Dunaway falls ill to a misdiagnosed kidney malady. She spends all her time in the hospital and Sinatra visits her at breaks in this case.

Frank delivers a very good performance in a role similar to the one he had in The Detective. He's supported by the rest of the cast very well, except with Anthony Zerbe's impossible role. Besides who I've mentioned look for a really nice turn by Joe Spinell as the mendacious doorman where suspect David Dukes lives. His role is similarly undefined, we really never learn why he's doing these crimes.