A 1961 science ficton film produced, directed, and co-written by Creator/IrwinAllen.
Earth's [[https://en.wikipedia.org/wiki/Van_Allen_radiation_belt Van Allen radiation belts]] have caught on fire, causing the global temperature to rise day by day, which threatens to end all life in three weeks. Admiral Nelson (Creator/WalterPidgeon), who has constructed an experimental nuclear submarine called ''Seaview'', sets out on a mission to restore he planet to its normal state.
The film became the basis for a [[Series/VoyageToTheBottomOfTheSea television series]] later in the decade.
!!This film has examples of:
* ArtisticLicenseAstronomy: The [[https://en.wikipedia.org/wiki/Van_Allen_radiation_belt Van Allen radiation belt]] literally catching fire. Enough said (let alone the whole "can be surgically fixed with a nuke" part).
* BerserkButton: Crane ''explodes'' when he finds Alvarez giving a sermon to the crew in the ''Seaview'''s mess room about how all their efforts will ultimately prove worthless and all that is left for them to do is to make their peace with God. As he puts it, what the crew needs least of all right now is to have some doom-sayer on board bringing their spirits down.
* CommunicationsOfficer: Sparks. He is the first to get very distressed when increment in atmospheric radiation makes it impossible to contact ''anybody''.
* CoolShip: The ''Seaview''. A fully-armed state-of-the-art atomic submarine that can outrun and outdive regular submarines, has an internal pool for sharks (or other sea creatures worth investigating)... and, oh, yeah, has a glass nose. The fact that it has the InUniverse nickname of "Nelson's Folly" showcases how little people thought of its technological advancements.
* CrazyEnoughToWork: The plan to nuke the Van Allen belt. Most of the drama between Nelson and [[UndyingLoyalty almost]] everybody else comes from the fact that Nelson is the only one that ''doesn't'' thinks this.
* DeusExNukina: To stop the world from turning into a dried husk, a nuclear missile must be fired to the Van Allen radiation belts from the Marianas.
* TheFundamentalist: [[spoiler:Alvarez believes that it's God's will that Earth should burn up, and is one of the two saboteurs onboard ''Seaview'']].
* GiantSquid: A gigantic octopus attacks the ''Seaview'' as it is nearing its goal, and is driven away by electricity. Earlier in the film, an actual giant squid attacks the divers repairing the transatlantic phone line on the ocean bottom.
* AGlassInTheHand: One of the many signs that the crew is growing increasingly uncomfortable with the whole situation is when one of them crushes a glass as he hears Admiral Nelson saying that the attempt to communicate with land via the underwater land line in the Atlantic didn't worked and, thus, will continue the expedition to the launch point and nobody will be able to talk to their families.
* GlobalWarming: When the skies start to burn, the ice caps melt while ''Seaview'' is in the Arctic Ocean, leaving chunks of ice to rain down on it (which ignores the fact that ice floats).
* HotSubOnSubAction: One of the many rapid-fire catastrophes that get in the heroes' way on the climax is the encounter of a couple of nuclear subs that have been sent to hunt down ''Seaview''.
* IgnoredExpert: Nelson, who proposes pulling the DeusExNukina (and insists that there is no time to argue), but is undermined by UN Emergency Scientific Meeting head delegate (and scientist) Emilio Zucco, who believes the "sky fire" will burn itself out. Nelson, thus, has to perform the expedition with everybody else thinking he's insane.
* InsufferableGenius: Admiral Nelson. It is this, and various decisions that (in Crane's eyes) make him look like TheNeidermeyer, that make the Captain a CommanderContrarian. The ''Seaview'' is even mentioned early in the film to have been nick-named "Nelson's Folly" by the news.
** Emilio Zucco as well. The U.N. Emergency Scientific Meeting devolves into an intellectual measuring contest with his insistence that his theory is right and Admiral Nelson is bonkers vs. Admiral Nelson's insisting that there's no time to sit down and wait to see if it's true.
* NumberTwo: Captain Crane, with some degree of CommanderContrarian to Admiral Nelson. For most of the film, he actually ''hopes'' that Zucco's theory is the correct one and Nelson is wrong.
* SeaMine: The submarine almost plows headfirst into a mass of underwater mines, and a tense sequence starts when they have to send in a minisub to remove one they got tangled with [[spoiler:that gets blown up when it accidentaly triggers a couple of them. The need to go around it (and thus lose time) adds to Nelson and Crane's ItsAllMyFault moments.]]
* SetTheWorldOnFire: Earth's Van Allen belts are on fire and if nothing is done about them, they will slowly roast the planet.
* SternChase: The moment Nelson storms out of the U.N. Emergency Scientific Meeting to get the ''Seaview'' to the Marianas, the world's governments try to stop him from doing something that they (erroneously) think will destroy the world. The mine field is one of such attempts, and the climax involves the (foreshadowed) attack of various subs ordered to sink ''Seaview''.
* ThreateningShark: ''Seaview'' has a pool inside it, where Lucius keeps a shark for his studies. [[spoiler:Late in the film, Dr. Hiller, one of the two saboteurs onboard, falls into it after a brief struggle with Capt. Crane and gets eaten]].
* TitleThemeTune: Sung by Frankie Avalon, who also plays Lt. Romano.