MI6 agent James Bond meets a Swiss banker to retrieve money for Sir Robert King, a British oil tycoon and friend of M. Bond tells the banker that King was buying a report stolen from an MI6 agent who was killed for it, and wants to know who killed him. The banker threatens Bond, but Bond overpowers him. The banker is killed by his assistant before he can reveal the assassin's name. Bond escapes with the money.
Back in London, Sir Robert is killed by the booby-trapped money inside MI6. Bond gives chase to the assassin – the assistant again – on a boat on the Thames to the Millennium Dome, where the assassin attempts to escape via hot air balloon. Bond offers her protection, but she refuses. She causes the balloon to explode, killing herself.
Bond traces the recovered money to Renard, a KGB agent-turned-terrorist. Following an earlier attempt on his life by MI6, Renard was left with a bullet in his brain which is gradually destroying his senses, making him immune to pain. M assigns Bond to protect King's daughter, Elektra; Renard previously abducted and held her for ransom, and MI6 believes that he is targeting her a second time. Bond flies to Azerbaijan, where Elektra is overseeing the construction of an oil pipeline. During a tour of the pipeline's proposed route in the mountains, Bond and Elektra are attacked by a hit squad in armed, paraglider-equipped snowmobiles.
Afterwards Bond visits Valentin Zukovsky at a casino to acquire information about Elektra's attackers; he discovers that Elektra's head of security, Davidov, is secretly in league with Renard. Bond kills Davidov and boards a plane bound for a Russian ICBM base in Kazakhstan. There, Bond, posing as a Russian nuclear scientist, meets American nuclear physicist Christmas Jones and enters the silo. Inside, Renard removes the GPS locator card and weapons-grade plutonium from a bomb. Before Bond can kill him, Jones blows his cover. Renard steals the bomb and flees, leaving everyone to die in the booby-trapped missile silo. Bond and Jones escape the exploding silo with the locator card.
Back in Azerbaijan, Bond discloses to M that Elektra may not be as innocent as she seems, and hands her the locator card as proof of the theft: an alarm sounds, revealing that the stolen bomb from Kazakhstan is attached to an inspection rig heading towards the oil terminal. Bond and Jones enter the pipeline to deactivate the bomb, and Jones discovers that half of the plutonium is missing. They both jump clear of the rig and a large section of the pipe is destroyed. Bond and Jones are presumed killed. Back at the command centre, Elektra reveals that she killed her father as revenge for using her as bait for Renard. She abducts M, whom she resents for advising her father not to pay the ransom money.
Bond accosts Zukovsky at his caviar factory in the Caspian Sea – which is then attacked by Elektra's helicopters. Later, Zukovsky reveals his arrangement with Elektra was in exchange for the use of a submarine, currently being captained by Zukovsky's nephew, Nikolai. The group goes to Istanbul, where Jones realises that if Renard were to insert the stolen plutonium into the submarine's nuclear reactor, the resulting nuclear explosion would destroy Istanbul, sabotaging the Russians' oil pipeline in the Bosphorus. Elektra's pipeline is planned to go around Istanbul, dramatically increasing the value of her own oil. Bond then gets a signal from the locator card from the Maiden's Tower – just before Zukovsky's underling, Bullion blows up the command centre. Zukovsky is knocked unconscious, and Bond and Jones are captured by Elektra's henchmen. Jones is taken aboard the submarine, which was seized by Renard's men. Bond is taken to the tower, where Elektra tortures him with a garrote. Zukovsky and his men seize the tower, but Zukovsky is shot by Elektra. The dying Zukovsky uses his cane gun to free Bond. Bond frees M and kills Elektra.
Bond dives after the submarine, boards it and frees Jones. Following a fight, the submarine starts to dive, and hits the bottom of the Bosphorus, causing its hull to rupture. Bond catches up with Renard and fights and kills him. Bond and Jones escape from the submarine, leaving the flooded reactor to detonate safely underwater.