A man named Kochak, a hoodlum who has illegally entered the United States aboard a tramp steamer, has been in the country — specifically, New Orleans — for only a matter of hours. He has already found an illicit poker game, lured there by his duplicitous cousin Poldi. Kochak is up $190 at the poker game when, suffering from flu-like symptoms, he tries to leave. Unfortunately for Kochak it isn't the sort of poker game you're allowed to leave with money in your pocket, so Blackie, the seething psychopath in charge of the game, sends Poldi and his other flunky Fitch (Mostel) after Kochak. When Kochak pulls a knife, Blackie shoots him to death.
It turns out that for Kochak, it didn't matter. The authorities pick up his corpse and take it to the morgue, and discover terrifying news: Kochak was suffering from pneumonic plague, a highly communicable and nearly 100% lethal illness. The bullets only shortened his life by about 12 hours. More importantly, Lt. Commander Clinton Reed of the U.S. Public Health Service (Widmark) realizes that pneumonic plague may be on the loose in New Orleans. A seemingly unimportant gangland slaying suddenly becomes hugely important as Reed goes on a desperate hunt for Kochak's murderers, before they spread the plague all over the city.
Film debut for Palance, who would go on to play many more psychos and murderers over a long career. Alfred Newman composed the music.
See also The Killer That Stalked New York, another film from the same year about a disease outbreak in a U.S. city, this time smallpox in New York City.
- Actually Pretty Funny: After one of the many times Reed and Warren butt heads, the following exchange takes place:Reed: You know, my mother always told me if you looked deep enough in anybody, you'd always find some good, but I don't know.
Warren: With apologies to your mother, that's the second mistake she made.
Reed: (chuckles) I should have seen that one coming.
- Back-Alley Doctor: Strongly implied to be the case with the shady doctor that Blackie calls for Poldi, who obviously is less concerned with helping Poldi than he is with helping Blackie get what he wants.Doctor: Unfortunately, I am persona non grata in most of the medical supply houses.
- The Black Death: Pneumonic plague. The more famous bubonic plague, which concentrates in the lymph nodes and killed off a third of Europe in the 14th century, is bad enough. But pneumonic plague is transmitted through the air, so anybody who coughs can infect everyone around, and it has a 100% mortality rate. Reed springs into immediate action while the rest of the authorities drag their feet.
- Blasting It Out of Their Hands: Warren saves Reed's life by shooting Blackie's gun out of his hand as Blackie is about to shoot Reed.
- Ceiling Cling: Blackie hides in the beams on the underside of the pier, and uses it to deliver a Tap on the Head to Reed when Reed comes searching for him.
- Chiaroscuro: Some arty black and white photography in the scene where Poldi and Fitch corner Kochak in an alley lit only by a single bright streetlight at the end.
- Cigarette of Anxiety: After bawling out the reporters and the mayor with a rant about how they're endangering the entire nation if they print the story about the plague, Reed goes over to Warren and says "Gimme a cigarette." An indulgent Warren says "Take the pack."
- Coincidental Broadcast: A previously silent radio erupts with a bulletin reporting that Mackey, Reed's superior, has announced the containment of an outbreak of plague.
- Establishing Character Moment: No better way to establish Reed as a Standard '50s Father than to introduce him with a scene where he and his little boy are painting a chest of drawers in the front yard.
- Explain, Explain... Oh, Crap!: Captain Warren says that even if the dead man did have the plague, the man who shot him hadn't been within 10 feet of him. Dr. Reed then asks him how the body ended up on the riverbank. Warren starts saying that somebody could have carried it there, and stops suddenly with an Oh, Crap! look on his face.
- Extremely Short Timespan: About 2 1/2 days from Kochak's murder to the apprehension of Blackie.
- Faux Affably Evil: Blackie's murderous sociopathy is possibly even scarier when he's putting on the charm to get what he wants, like when he's buttering up Poldi's sister or telling Poldi's mom that they only want to find him so they can get him a doctor.
- Fire-Forged Friendship: Reed and Warren start off snarling at each other but by the end, when the outbreak has been contained, they've formed a friendship.
- Fruit Cart: A variation, as Blackie and Fitch steal a fruit truck when trying to escape. Fruit eventually spills everywhere when they crash the car.
- Have You Told Anyone Else?: Done very subtly, and in a non-fatal way, by Captain Warren. Neff the reporter has put all the pieces together and says he's going to run with the story. Warren says "If your editor has the story, let him go ahead and print it." When Neff shoots back "He doesn't have the story yet, but he's going to get it," Warren has Neff arrested so he can't break the story.
- Headlock of Dominance: Blackie applies a disturbing one to his ill flunky, half-cradling him and half-threatening.
- I Always Wanted to Say That: A variant. Reed's wife, fed up with his coldness and distance, reads him the riot act about how he can't disregard her feelings to the degree he has. Reed, knowing that she's right, asks her how long she's been planning the speech. She admits it's been a while.
- Intrepid Reporter: Neff, the reporter who sniffs out something weird going on and discovers the story that Reed and Warren are trying to keep secret. Reed and Warren have him arrested to keep the secret a secret, but not before Neff makes some pretty good points about how the public has a right to know about the plague in the city
- Never Bring A Knife To A Gunfight: A sweaty, coughing Kochak still has enough energy to pull a knife on Poldi and Fitch. Blackie promptly shoots him to death.
- Obstructive Bureaucrat: The mayor and the rest of city authorities are skeptical and have to be prodded into action by Reed. Captain Warren of the NOPD is especially hostile, but there's a reason: he hates doctors after a doctor misdiagnosed his late wife's brain cancer as neuralgia.
- Overly-Nervous Flop Sweat: Fitch can often be seen mopping that great big bald dome of his. In one scene where Fitch is frantically apologizing after Poldi gets away, Blackie says "All right, don't get sweaty."
- P.O.V. Cam: The entire opening credits are shot over a POV cam as a car goes down what looks like a Red Light District.
- Significant Background Event: An audio version. As Reed and Warren are fruitlessly chasing a dead-end lead down by the docks, the police radio sparks with chatter about a woman down with fever. Moments later a frantic cop shouts out to Warren about the call and Reed and Forest tear off in pursuit of the new case.
- You Have 48 Hours: "We have 48 hours", says Reed, as he desperately tries to make skeptical authorities realize the dire necessity of catching Kolchak's killers before the plague is spread all over the city.