He stood at the window of the villa, looking out over the garden, when the room fell silent behind him. He had been summoned here, to his Abwehr controller’s house in Lisbon, and now he sensed rather than heard the other man enter the room. A voice came from behind him, low and deliberate. Don’t move.

Don’t turn around. His hand slid toward the pistol in his pocket. He was certain this was the end. Years of playing both sides had finally caught up with him.

His fingers closed around the cold metal. Then he saw it—the reflection in the French windows. Von Karsthoff was standing behind him with a tiny pet monkey perched on his shoulder. The tension broke in a moment that was almost absurd.

He had not been discovered. Not yet. Von Karsthoff had news, and it was terrible. Neutral Yugoslavia had been bombed and invaded by Germany.

For Dusko Popov, born in Dubrovnik and now officially on the German side, that meant his entire family was in danger. If the Gestapo ever discovered his double game, they would show them no mercy. But there was more. Berlin had issued new orders.

Hitler was preparing for war with America. The Abwehr was to build a new spy network in the United States, and Popov—one of their most trusted agents—had been selected to lead the mission. The Double Cross Committee in London received this news with dismay. Popov was their most valuable asset, the only double agent with direct, face-to-face contact with the Germans.

But Popov had an idea. He explained it to them at their headquarters, and it was so simple it astonished them. He had convinced the Abwehr he ran a network of agents in Britain, and he had told them he was paying these fictitious agents out of his own pocket. Now he would tell them the costs were too high.

The Abwehr would take over the payments. Popov would launder the money through the United States and route it directly to MI6. The Germans would be funding British intelligence, cash flowing straight into their coffers. They called it Plan Midas.

Popov returned to Lisbon to sell the idea to Von Karsthoff. It worked. Von Karsthoff agreed to provide the cash before Popov’s departure. In return, he handed Popov a single sheet of typewritten paper.

It was just an ordinary letter. Popov asked what he was supposed to see. Von Karsthoff said all the information was on the piece of paper. It was the first anyone had ever heard of microdot technology.

A complete dossier of questions about the American military had been hidden beneath a full stop, reduced photographically to a size invisible without a microscope. Von Karsthoff called for a bottle of champagne, and together they toasted Popov’s new assignment. Before leaving for the United States, Popov contacted his old friend Johnny Jebsen one last time. Jebsen told him something that did not sit right.

He had been asked by the Abwehr, on behalf of their allies the Japanese, to travel to the port of Taranto in Italy. He was to find out why a recent British air strike had been so successful. The attack, Jebsen explained, had been launched entirely from aircraft carriers. Popov was puzzled.

Why were the Japanese so interested in an operation launched from carriers? He looked again at his American mission questionnaire. It requested detailed information about a U. S.

Naval base in the Pacific called Pearl Harbor. Why would the Japanese want to know about that base? And why were they so interested in attacks from aircraft carriers? He put two and two together.

The Japanese were planning to attack Pearl Harbor. There was now a real urgency to his journey. On the tenth of August, 1941, Popov collected the equivalent of forty thousand dollars from Von Karsthoff for Plan Midas and boarded a plane for America. When he landed, he went straight to the headquarters of the FBI.

The British had told them he was coming. The reception was not warm. The FBI was run by J. Edgar Hoover, a man who considered himself above the law and trusted few people, particularly foreigners.

Hoover believed that being a double agent made Popov doubly untrustworthy. He refused to meet him and sent a team of agents to interrogate him instead. The agents were fascinated by the microdot technology. They were not at all interested in Pearl Harbor.

Popov was treated with suspicion and ordered to leave. From then on, he was followed and watched wherever he went. It went on for weeks. He could not warn the FBI about Pearl Harbor, and he could not conduct his fake spying activities for the Abwehr either.

It was an impossible position. To take his mind off the FBI, he flew to the ski slopes of Sun Valley. He skied from early morning until dark. It did not work.

His nights passed in a blur of alcohol and sex. It was easier to grin in company than to sob alone in New York. He returned to New York and, at a party, ran into an old friend from before the war—the Hollywood star Simone Simon. They renewed their pre-war relationship and began a passionate affair.

They were seen at all the big New York parties, and since Popov was running out of money, Simon funded his champagne lifestyle. Then, out of the blue, the FBI contacted him. Hoover wanted to see him. Had his message about Pearl Harbor finally got through?

On the twenty-fourth of September, Popov walked back into the FBI offices in New York. He was escorted to a small back office. Hoover sat at a desk. He did not get up.

There were no introductions, no preliminaries. He ordered Popov to sit down and began to rant, pounding the desk with his fist as he attacked his reputation. Popov refused to leave. He lit a cigarette and began a spirited defense, describing the microdot questionnaire and warning Hoover of the plot against Pearl Harbor.

Hoover accused him of being a German agent. You are begging for information to sell to your German friends, he said, so you can make money and be a playboy. Popov was seething. He tried to defend himself, but Hoover had heard enough.

Are you trying to teach me my job? Popov got to his feet and snapped that he did not think anyone could teach Hoover anything. He stormed out and slammed the door. He walked away with a knot in his stomach.

Hoover, he later wrote, acted as though it were his divine right to fabricate whatever tale he pleased. Popov soon forgot his detractors when a telegram arrived from Lisbon. He was to meet Von Karsthoff’s assistant Elizabeth in Rio de Janeiro. He flew to Rio at the end of October and spent many days in meetings with Elizabeth and Abwehr agents.

They were not concerned that he had made no contact with his German handlers in Lisbon, nor that he had made no progress on the Pearl Harbor questionnaire. They gave him new instructions and a new questionnaire, again hidden beneath a microdot. His mission now was to investigate why the Americans were so keen to find sources of uranium ore in South America. He had no idea that both America and Germany were racing to produce nuclear weapons.

Popov decided to return to New York by sea. Three days from port, shocking news reached the ship. The Japanese had attacked Pearl Harbor. Japan was almost four thousand miles from Hawaii.

The 353 aircraft that launched the surprise attack had flown from aircraft carriers. Twelve U. S. warships were sunk.

One hundred eighty-eight aircraft were destroyed. Almost two and a half thousand personnel were killed. Popov’s warning had fallen on deaf ears. And he had more to worry about.

At Bletchley Park in England, British intelligence had cracked the Enigma code, the top-secret cipher the Germans used to communicate. The codebreakers now intercepted chatter about Popov from the Abwehr. He had not been in contact since his meetings in Rio weeks earlier. The Germans had grown suspicious and were questioning his loyalty.

But the British could not alert Popov without revealing their codebreaking operation. They let him return to Portugal to face the music. When he arrived in Lisbon, he found Von Karsthoff had been joined by another Abwehr controller. Together they questioned him harshly.

Why had he not carried out any of the tasks they had requested? Popov stayed supremely calm and told them all manner of stories to explain his inactivity in the United States. Had the Germans believed him? Three days later, a message was sent to Berlin.

It was intercepted by the British at Bletchley Park. The message stated that Popov could still be trusted. The British were astonished, and jubilant. Best of all, the Abwehr allowed Popov to resume the Lisbon-to-London shuttle.

He had not been back to London for two years. The city was vastly different from the one he had known in the winter of 1940. Despite the battering it had endured at the hands of the Luftwaffe, Londoners were cheerful and optimistic. The tide of the war was turning.

By October 1942, Germany was in trouble. Defeat seemed only a matter of time. The Allies were planning a counterattack, the beginning of the end for Hitler. It was to be called Operation Overlord—D-Day.

Key to its preparation was Operation Fortitude, a plan for mass deception prepared by the Double Cross Committee. Popov played a central role. The Allies did not want Hitler to know the invasion would land on the Normandy beaches. They built hundreds of decoy tanks and aircraft, knowing they would be visible from German spotter planes, and placed them in strategic locations to convince Hitler the invasion would come at Calais, or even Norway—anywhere except Normandy.

Popov’s job was to feed the Germans the information that completed the picture. Once the Germans had that entire picture in their minds, they would not be looking in the right place when D-Day came. On his final trip to Lisbon, Popov presented Von Karsthoff with a dossier on the Allies’ order of invasion. It contained misleading information about troop numbers in Britain, giving false locations for three armies, three army corps, and twenty-three divisions—more than half a million men.

On the ninth of March, Bletchley Park intercepted an Abwehr message describing Popov’s intelligence as reliable. As a consequence, fifteen divisions—almost a quarter of a million German soldiers—were rerouted to Calais. The whole trick was to convince the Germans of his loyalty so that when the day of the big lie came, they would swallow the pill that much easier. As Popov made his way back to London for the last time, he carried intelligence about new German secret weapons.

Von Karsthoff had warned him to stay out of London because, in the coming weeks, Hitler would unleash his new terror weapon on the British. Popov gave MI6 the dates of the first attacks by the V1 flying bomb. But with Operation Overlord just five weeks away, disturbing news reached Bletchley Park. Popov’s friend Johnny Jebsen had been kidnapped in Lisbon by the Gestapo, who were investigating his finances.

The Double Cross Committee was concerned that Jebsen might blow Popov’s cover and jeopardize the deception plan for Normandy. But it was too late to postpone. On the sixth of June, 1944, 175,000 Allied troops landed on the Normandy beaches. Were they walking into a trap?

Had Operation Fortitude worked, or had Johnny Jebsen cracked under torture? Jebsen had been tortured by the Gestapo. He had not uttered a word about his true identity or about Popov. D-Day was the beginning of the end for the Nazis.

In London, Popov was invited to a celebratory dinner and given the seat of honor. It was announced that he would be awarded the Order of the British Empire. But Popov was in no mood to celebrate. He learned that Johnny Jebsen had been shot dead while trying to escape—a common euphemism for murdered.

Johnny’s death was a heavy blow. They had watched each other’s backs throughout the war and achieved important things together. Hate rose in Popov like fury. He wanted vengeance.

After the war, as the Third Reich collapsed, Popov embarked on his last mission. He got hold of a British officer’s uniform and traveled to Germany, where he had the honorary rank of lieutenant colonel. He scoured the country, inspecting every prisoner of war camp, trying to track down the man responsible for Jebsen’s murder. One name kept coming up.

Walter Sulzer, a member of the German intelligence service, had been commandant of the camp where Jebsen was killed. In Popov’s eyes, he was Johnny’s murderer. Popov tracked him down to the northern town of Minden. There was no one home at the address, so he broke in and waited.

When Sulzer came through the front door, Popov confronted him. He took him to nearby woods and forced the barrel of his pistol deep into his mouth. Could he kill again? He knew he would not, could not.

He vomited his sins and his shame and his pain. Dusko Popov had started the war as a wealthy playboy, an incorrigible womanizer, and a dedicated gambler. He ended it as one of Germany’s most trusted spies and one of Britain’s most successful double agents. He fed the Germans a constant stream of doctored military intelligence.

His Midas plan drained the Abwehr of $85,000—over two million in today’s money—almost the entire cost of running the Double Cross Committee. His warning about Pearl Harbor may have fallen on deaf ears, but his deception skills were vital to the success of D-Day. What Popov achieved during the war was to constantly befog the minds of German intelligence. He confused them, made them think things were happening that were not happening, and that things that were happening were not happening at all.

Could Popov really have been the inspiration behind Ian Fleming’s James Bond? Fleming, a British agent who kept an eye on Popov at the casino in Lisbon, witnessed his behavior at the roulette and baccarat tables. But the comparison would downgrade his effort. What he did during the war, along with the rest of the Double Cross gang, was quite amazing.

The James Bond association is practical, but not very honest. When he returned to Britain after his attempt to avenge Jebsen’s murder, Popov was granted British citizenship and awarded his OBE. The presentation was made appropriately, in the cocktail bar at the Ritz.