Billion Dollar Brain

A mechanical voice over the phone orders Harry Palmer to take a package to Helsinki. The package is said to contain six virus-laden eggs stolen from Porton Down. This summons him into a global conspiracy that will push him back into covert operations.

In Helsinki, Anya introduces Harry to Leo Newbigen, an old MI5 contact who is secretly in love with Anya. Harry senses that Anya is not reciprocating in sincerity. The atmosphere is tense with competing loyalties.

Harry realizes he cannot trust Leo or Anya. Colonel Ross, his former MI5 superior, abducts him and coerces him back into the British government operation. The assignment shifts from a simple delivery to a high stakes pursuit.

Leo leads Harry to a secret room where a computer issues daily instructions to the local team, speaking in the same mechanical voice that summoned him. The computer orders Leo to kill Anya, but Leo refuses to carry out the hit. The tension among the trio deepens as loyalties fracture.

A scientist assesses the eggs to determine their value and potential use in the wider scheme. Harry is formally introduced as a new operator within the conspiracy. The stage is set for his deployment on a multinational mission.

Harry is sent to Latvia to join rebels and collect intelligence. He is captured and left for dead, only to be freed by Colonel Stok, an old KGB associate. The rescue reens him back into the dangerous web of espionage.

Back in Helsinki, Anya tries to kill Harry by seduction, but he sees through the ploy. She confesses that the computer told her to kill him. Harry locks her in a room and waits for Leo at the computer.

Leo offers to pay Harry off for his trouble, but Harry demands half of the money Leo is siphoning from the conspiracy. The dispute drives a deeper wedge between them, yet they still pursue the same objective. They agree to continue the partnership for now.

The pair travel to Texas to meet oil tycoon General Midwinter, who displays a vast computer network that issues orders worldwide. Midwinter plans a Latvia rebellion and a broad confrontation to trigger a global crisis. Leo's greed becomes apparent as the scale of the operation grows.

Midwinter realizes that Harry is a double agent, but Harry argues that Leo is manipulating events to enrich himself. The two form a fragile alliance to locate and stop Leo before the conspiracy goes too far.

Leo and Anya board a train bound for Moscow with the eggs. Harry, accompanied by Midwinter's men, intercepts the train and forces Leo off. Anya shoots Harry's bodyguards as the train pulls away and then takes the eggs, revealing her betrayal.

Midwinter leads his private army across the Gulf of Finland into Latvia in crude convoys. Stok orders bombers to hit the route by dropping bombs on the ice, causing the convoy to plunge into freezing water. General Midwinter sinks with the rest of the fleet.

Harry awakens alone on an ice floe after the disaster. Stok arrives in a helicopter with Anya, revealing her as his agent. He gives Harry the eggs and says they have their own ideas for moving forward.

Back in London, Harry delivers the eggs to Colonel Ross, who promises a promotion as a reward. When he opens the package, he finds it is filled with chicks instead of eggs. The final twist underscores the theme of deception in espionage.