Orbiting over the Earth is Jupiter 16, a US space capsule manned by two astronauts. As they maintain radio contact with bases in Hawaii and Houston, one of the astronauts ventures outside to make routine repairs, when radar picks up another spacecraft closing fast. Radio contact is lost and the spacecraft opens up and swallows Jupiter 16, in the process severing the other astronaut's lifeline and leaving him to die in space.
In Hong Kong, James Bond is enjoying a romantic encounter with a Chinese woman. She leaves the bed a pushes a button that levers it into the wall. Two men burst into the room with machine guns and spray the bed. When the police arrive, the woman has disappeared and Bond is found dead.
A contentious meeting between US and Russian diplomats follows, brokered by a member of Britain's foreign service. The US believes the pirate spacecraft is Russian in origin, having tracked the ship in orbit before it ventured into the atmosphere; the US is to launch another capsule in three weeks and will regard interference with the ship as an act of war, and will launch a military attack on Russia should the capsule come under attack itself. Great Britain, however, believes the alien ship landed in the Sea of Japan based on tracking of the ship from a station in Singapore, and that a British official in Hong Kong is following this lead.
MI6's best agent, James Bond, is ordered to investigate. His assassination in Hong Kong was a ruse to trick his enemies into believing he was dead so he can continue his mission undetected. He is ordered to Japan to meet with members of Japan's SIS. One, a beautiful woman named Aki, takes him to the home of Dikko Henderson, a British intelligence official living in Japan who has discovered information about the rogue spacecraft. Henderson theorizes that a third power is using Osato Chemicals, a vast multinational corporation, to launch spacecraft from Japan to attack US and Russian spacecrafts and trigger war between the two superpowers. However, Henderson is stabbed to death before he can reveal more. James subdues Henderson's killer, then takes his place and infiltrates Osato Chemicals to find more information. He battles with a large bodyguard and defeats him before he finds a safe containing paperwork and a film negative that he takes before being pursued by security guards.
James is rescued by Aki, but he is now mistrustful. When Aki stops her car near a subway entrance James chases her, only to fall into a "trap" set by "Tiger" Tanaka, the head of Japanese SIS and the most secretive official in Tokyo. After verifying Tanaka's credentials via a codeword, James works with him and they examine the paperwork found in Osato's safe. It details the smuggling of LOX - technical shorthand for liquid oxygen for rocket fuel and which is also the name for smoked salmon, and the perfect cover. The film negative is of a supertanker, the Ning Po, the picture coming from an American tourist killed by whoever works for Osato Chemicals; the picture shows not only the ship but a small boat of fishing women, indicating the area is an outer island on the way to Shanghai. James theorizes that the international criminal consortium SPECTRE has a role in the space hijackings given their history of using private organizations for the actual legwork of a conspiracy in the service of other foreign powers.
James spends the night at Tanaka's house, where he is given exotic hospitality in the form of being bathed by "very sexiful" young ladies and given a relaxing massage by one. James' massage is taken over by the shapely and scantily-dressed Aki, who has fallen in love with him, a love the two consummate.
The next day James is arranged to meet with Mr. Osato in the guise of businessman Jim Fisher to negotiate a bulk-purchase of important chemicals. Osato surreptitiously X-rays James, finding he is armed, and James is given a drink by Osato's secretary, Helga Brandt, who is more than just an efficient aide-de-camp. Osato orders hitmen to kill James, but he and Aki escape and Tanaka dispatches the hitmen via a transport chopper sporting a giant magnet.
Tanaka radios James and orders James and Aki to Kobe, where the Ning Po is being loaded for departure. James then urges Tanaka to contact M in London to dispatch "Little Nellie" and her father - a minicopter gunship built under the supervision of Major Geoffrey "Q" Boothroyd. After arriving at Kobe, James and Aki find tanks of liquid oxygen but the two are attacked by a gang of dockworkers. James fights them off to allow Aki to escape, and it appears James himself will get away - until he is ambushed and knocked unconscious.
He is bound to a chair in Helga's room on the Ning Po, where she questions him about snooping around the dock and holds a plastic surgeon's instrument dangerously close to James to pry information from him. But she is also aroused by James' masculinity and allows herself to be seduced by him; after consummating their arousal she flies James in a private plane, then bails out and locks him in, but James manages to escape, land the crippled plane, and escape before it explodes.
Returning to Tiger's house, James is given photos of the Ning Po showing she stopped at an outer island and offloaded an enormous stockpile of equipment, shown by a vastly lower waterline. The threesome meet "Q" and Little Nellie is assembled by Q's crew of specialists. Sporting a variety of powerful weapons aboard Little Nellie, James overflies the area islands and is attacked by four gunships which he shoots down and which leave no doubt as to the presence of SPECTRE.
A scheduled Russian space shot, meanwhile, goes off, and is grabbed by the enemy rocket, which is tracked by the US Air Force before disappearing, seeming to confirm to the US that the Russians are behind the space hijackings and will now use the excuse of losing their own spacecraft to shoot down the next Jupiter launch.
Both Osato and Helga Brandt meet with their leader in his headquarters after the rogue craft returns to it's base. The man's face is not shown however he holds a white cat and finishes a meeting with two scientists who designed the radar jamming system that has cloaked the location of the villain's base. Both men demand more money but acquiesce after his bodyguard, Hans, shows them his leader's pool of piranha. The two scientists leave and the mysterious villain flashes the x-ray showing Bond's Walther PPK and expresses his disappointment in both Osato and Brandt for failing to kill him. Both accuse each other of failure. The villain orders Brandt to leave and drops her into the piranha pool as she walks across its bridge; she is eaten alive. He then sharply orders Osato to kill Bond immediately.
Bond is ordered to report to Tiger's palatial estate which also doubles as a ninja training camp. Tiger's plan is to use his army of men to infiltrate a fishing village on the island where the Ning Po last made port. Bond himself will be disguised as a Japanese man and will train with the rest of Tiger's ninja army; the army will later hide in the island's largest village as local fishermen. Bond will also take a wife; to his dismay, Aki will not be the woman because she is not from the village. After the procedure which disguises him, Bond and Aki spend the night together. While they sleep, an assassin sneaks into the rafters above their bed and lowers a needle on the end of a thread. He trickles a powerful poison down the thread, his target being Bond. Bond, however, shifts in his sleep. Aki also shifts at the same moment and the poison drips onto her mouth. As she struggles and dies, Bond wakes up and shoots the assassin dead. Tiger comes in and Bond tells him what happened. Bond seems more urgent than ever to investigate the plot but Tiger tells him he needs a few more days of training. The next day during a staff match, Bond is attacked again by another assassin who tries to stab him with a knife hidden in his weapon. Bond kills the man and Tiger identifies him, saying he's not one of his men. The next day Bond is wed to a lovely young woman from the fishing village, Kissy. The settle into a small house in the village and Kissy rejects Bond's advances to consummate their marriage. The two also notice a small funeral being held for a young girl who'd been exploring a nearby cave along the shoreline. When the girl's boat floated out of the cave, she was mysteriously dead. At early morning, Tiger warns Bond that the Americans are launching their next spacecraft today with a last warning to the Soviets! Bond becomes interested in the cave; the next morning, he and Kissy drift away from the fishing fleet and explore the cave. When they enter it, Bond immediately notices that a poison gas has been released in the cave and they jump over the side of their boat and swim inside. The come ashore and hike up to the volcano's caldera. They see a helicopter fly down into the basin but it disappears. A closer investigation reveals that the surface of the crater's lake is actually a gigantic metal cover that hides a secret base where the rogue rocket has been hiding after swallowing the USA and Russian spacecraft. Bond sends Kissy back to find Tiger and his men, while Bond himself sneaks into the crater.
Inside the volcano, Bond locates the missing astro- and cosmonauts being held prisoner. They subdue a few guards and imprison the astronauts that are next to fly into space and capture the next spacecraft launched by the USA. Bond takes the place of one of them, in the hopes that can sabotage the next capture, however, as he prepares to enter the rogue rocket, he's stopped at the last moment and taken to the volcano's command center. There he meets the mysterious villain; Ernst Stavro Blofeld, leader of SPECTRE, a vast criminal organization. Bond's personal effects are confiscated and Blofeld reveals his plan; the capture of both American and Russian spacecraft will trigger a nuclear war between the two, eliminating them from the world stage. Presumably China would move in and seize control of the world from the two superpowers. As Blofeld's craft moves into position, Bond asks for a cigarette, one of the weaponized ones given to him by Tiger. He kills one of Blofeld's men with the miniature rocket inside and escapes from the control room as Tiger's ninja army arrives at the crater. A fierce battle erupts. Bond and Tiger's men eventually gain the upper hand in battle. Bond finds a way into the control room through Blofeld's private quarters. There Bond battles briefly with Hans until the henchman is thrown into his boss' pool of piranha. Bond reaches the control room and struggles briefly with the detonator for Blofeld's spacecraft until he is able to destroy the craft. Relieved, the POTUS calls off the nuclear run. Blofeld himself escapes after killing Osato and triggers a self-destruct device that cause the volcano to erupt. Tiger, Bond, Kissy and the ninja army escape into the sea.
Bond and Kissy find a life raft waiting nearby and board it. Bond asks Kissy if it's OK to take their "honeymoon" now and she agrees. As they kiss, a British sub surfaces underneath them and the raft is caught on the fore section of the sub. Inside, M orders Moneypenny to tell Bond to report.