by Howard Blum
Each day and long into the night, the team struggled to solve the same vexing problem: deciphering the encoded German military communications. But after two long years of harnessing their talents and ingenuity to the challenge, they could not break the cipher. Their mathematics could not, the frustrated young Poles acknowledged, perform the thousands and thousands of calculations necessary to get even a start on a solution.
The German engineers had adapted a 1920s commercial “secret writing mechanism to frustrate inquisitive competitors” called the Enigma to encode the nation’s military and diplomatic message traffic. And the demoralized Polish team was now ready to concede that the original marketers had chosen an appropriate name: enigma was the Greek word for “puzzle.”
At a glance, the Enigma machine seemed to look—and work—like a typewriter. However, when the operator hit a letter on the keyboard, this released an electric current that traveled back and forth through reflectors to a series of scrambling elements. The first letter in a word, A, for example, might come out as Z. And so on for each individual letter. The machine, in effect, translated sentences into a language that only another Enigma device—and one set that day to speak the identical tongue—could understand.
The scrambling elements were the inspired heart of the machines. There were three movable wheels, a miniaturized plug board that worked like a switching station in a telephone office, and a ring marked with the twenty-six cardinal letters of the German alphabet—omitted were vowels with umlauts—that ran around the rim of each wheel. Working in tandem, these mechanisms could transform the messages sent by the machine, awed cryptologists later estimated, into 150 million million million possible permutations.
Once encoded, the message would be transmitted in Morse code by a radio transmitter. Intercepting these signals was easy enough; the Poles, as well as the British and French, routinely grabbed Germany’s message traffic out of the ether. But it didn’t do them any good. Unless the recipient had another Enigma machine and, equally crucial, knew the designated daily settings for the device’s internal scrambling mechanisms, deciphering the code was impossible. A message remained tightly locked behind an impenetrable wall of seemingly meaningless blocks of letters.
But then in December 1931, just as they were ready to throw up their hands in defeat, the Polish Cipher Bureau wranglers gained their first insights into how the machine worked. Mathematics, though, had very little to do with this preliminary breakthrough. Two other fundamental principles conspired to move things forward—greed and sex.
HANS THILO SCHMIDT, A MARRIED forty-three-year-old official at the German Defense Ministry Cipher Office, had stumbled into an affair with his family’s maid. It was a totally unexpected bit of excitement, and it only piqued his appetite. He began looking for other extramarital dalliances. And he found them—at an unanticipated price.
An interlude of courting, he discovered sadly, was required before he could coax fräuleins into the bedroom. Champagne-fueled dinners and gaudy trinkets were costing him a bundle. And piling on to that teetering mountain of bills, there was the love nest he had rented and ostentatiously furnished to set the mood for these assignations. A middling bureaucrat’s salary could not stretch far enough to cover such an expensive hobby, especially when he was already supporting a demanding wife and two children.
Schmidt knew he would either have to give up his womanizing or find a way to make some extra money. With brisk pragmatism, he made his choice: he would earn a fortune by betraying his country.
Schmidt wrote a letter to the Deuxième Bureau, the organization that handled France’s intelligence operations, declaring that he had important German government documents to sell. Weeks later, in a hotel room in a small Belgian town near the German border, he handed over to a French secret agent the manuals explaining how to operate the German army’s Enigma machine.
In Paris, curious French cryptologists earnestly pored over the manuals, finally admitting defeat. The instructions, they complained, explained how to encipher a message, but gave no information that could be used to read a coded transmission.
In a rare fraternal gesture, the Deuxième Bureau charitably passed on the purloined manuals to MI6’s man in Paris. Full of great expectations, he sent them across the Channel to the Government Code and Cypher School, located two floors below the Service’s headquarters at 54 Broadway. After all, in the last war these wranglers had broken the previously “unbreakable” German code. This time, however, they found themselves for once agreeing with the French: Enigma could not be cracked.
Yet this second defeat only fueled the resolve of the tenacious head of the Deuxième Bureau cipher section. He’d paid 10,000 marks for the manuals—the equivalent of about $50,000 at the time—and he was determined to get some return for his lavish investment. Some brainy Poles, rumor had it, were poking at the Enigma machine; he decided he might as well let them have a look too.
Still, it was with little hope that he took the manuals to Warsaw and hand-delivered them to the army major who headed the Cipher Bureau. Perhaps these might be helpful, the French spy suggested. Maybe they’d spark an idea or two.
After consulting with the young team working in the Black Chamber, the major reported back. His message was deliberately guarded; he was a soldier by training and a Pole by birth, and both had schooled him to distrust the French. A few things here that interest us, he said mildly. But what my boys really need is a copy of the current Enigma settings the Germans are using. Think you might be able to get your hands on that?
The request was passed on to Schmidt by his handler. More money was exchanged, and within the month the specified documents were sent by diplomatic pouch to Warsaw for the major’s attention. Once they were delivered to the Black Chamber, the team eagerly went back into battle.
Working conscientiously, with a slow, methodical determination, they forged on. Over the next year, the French passed on additional manuals Schmidt had stolen, and more pieces were fitted into the puzzle. Soon the team’s shaky guesses were replaced by firm hypotheses, and then, miraculously, by proven theories. They were beginning to understand how the machine performed its magic.
IN THE AUTUMN OF 1932 a trio of the Chamber’s most gifted young mathematicians were ordered to Warsaw. It was now agreed that there was only one way to break the code: they would need to build their own Enigma machine from scratch. In a secret facility hidden in the Kabachi Woods, ten kilometers from the bustle of Warsaw, they went at it.
Working around the clock, they constructed a prototype in about six months. But one machine, they soon realized, was insufficient; enciphered messages could only be accurately decoded after they were received by another machine with identical settings. But how could they predict the settings? It was impossible; the scrupulous Germans changed them daily. The practical solution would be to construct an Enigma device that allowed the encoded message to be simultaneously read through a variety of different settings.
This insight snuck up on Marian Rejewski, one of the team members, as, looking for some small comfort at the end of a tedious day, he was studiously licking the ice cream from a bombe glacée off a spoon. In tribute to this eureka moment, the bomba was christened in the winter of 1934.
It was a network of Enigmas, a group of machines wired together, their many wheels and rings adjusted to a range of settings. The broad theory was that once an encrypted message was typed into the bomba, the message would travel through the network until ultimately it was read by an interconnected Enigma with the corresponding settings. And after weeks filled with frustrating trial and error, it finally worked.
The Polish team had broken Enigma.
For the next five years, the Poles read the encoded messages sent by the German military.
They did not inform the French whose spy had, at great risk, on at least six occasions, passed on the manuals and settings essential to their understanding of the wiring of the machine. And despite assurances made to the British cryptologis
ts, they never told them either.
The Poles kept their breakthrough a closely guarded secret.
BUT IT IS THE BUSINESS of espionage, as well as the nature of spies, not to trust anyone. The most rudimentary tradecraft assumes that every promise will be broken. And so while the donnish codebreakers at Britain’s Government Code and Cypher School innocently accepted the Polish team’s assurance that any Enigma discoveries would be swiftly shared, the Secret Intelligence Service was not so gullible. Their agents were covertly scurrying about, trying to find out whatever they could about Enigma.
The significance of the machine had first been brought to the Service’s attention by several valued sources. But as the likelihood of a war in Europe built to a gloomy certainty, one intelligence asset reiterated, and then kept doggedly pressing in his assertive, self-important way, that the secrets of the Enigma machine had to be unraveled. It was, he insisted, the key that could unlock the Nazis’ most carefully guarded plans. Among the many voices in the intelligence community preaching that Enigma would be of incalculable wartime value, William Stephenson’s was arguably—and he would later be the first to make this self-serving argument—the loudest.
Stephenson was a Canadian who, with his inventions and a shrewd business sense, had made a fortune in electronics after World War I. He settled regally in London, bought a grand country estate in the Chilterns, and, still restless, eager for new worlds to conquer, cannily branched out into a variety of businesses.
In the 1930s Stephenson’s investment in the Pressed Steel Company had him frequently shuttling off to Germany to buy steel. It was in the course of these business trips that he slowly came to a troubling realization: Germany was covertly allocating nearly all the steel it produced for the manufacture of arms and munitions. This was a violation of the Treaty of Versailles signed after World War I. But more importantly, he feared, it was indicative of the Nazis’ intentions for a not-too-distant future.
Back in London, Stephenson shared what he had seen with the Industrial Intelligence Center, the government organization monitoring foreign nations’ preparations for war. Major Desmond Morton headed the center, and the old-school soldier was impressed with Stephenson’s well-documented report, as well as with the pugnacious self-made millionaire. The major, who knew everyone who mattered, made sure that Stephenson’s detailed warning was passed on to his close friend Winston Churchill as well as the crown heads of intelligence who reigned on Broadway.
It was in this way that Stephenson—not unlike young Betty in her adventurous days in Spain—was recruited as an asset. He wasn’t a British agent, but the spymasters gave him the opportunity to get deeper into the secret world: in the course of your travels in Germany, they said, if you see or hear anything that might be of interest, give us a holler; we’d be eager to hear it.
Stephenson had many contacts in Germany. He dined in feudal splendor at the schloss of Fritz Thyssen, the steel magnate who was one of the early supporters of Hitler. He strolled through the sinister gray streets of Berlin with Charles Proteus Steinmetz, the wary Jewish scientist’s eyes darting about with suspicion, Stephenson would recall, as they headed down every block. He made sure his trips were busy, a whirl of factory meetings and black-tie dinners. He lived his cover. Yet he was always the secret agent, watching, listening. And so, without trying, he learned about Enigma.
It was a small indiscreet moment. One of his German hosts, bursting with Gemütlichkeit and fueled by schnapps, brought it up out of the blue. Remember those damn Enigma machines? he asked. Didn’t you give them a look years ago, and then decide they weren’t right for your organization?
Yes, Stephenson agreed, it was a bit too much fuss for the sort of messages we send. More trouble than they were worth.
Well, the German went on, as if amused. Guess who’s using them now? The Wehrmacht! Retooled the machine, and now they swear by it. Encode all their communications with Enigma.
That so? Stephenson said mildly. And then the conversation turned in another, long-forgotten direction.
Like many successful men, Stephenson was convinced he could instinctively appraise the value of a secret as soon as he heard it, whether it was a stock tip or the odd snippet of gossip. And he was a patriot. He also had his brief; and quite possibly he was already envisioning his own dashing future as a player of the Great Game. When he returned to London, he enthusiastically passed on this nugget—small, but solid gold, he was convinced—to his new friend Major Desmond Morton, and then to the Service.
But Stephenson didn’t consider his mission complete with a single report. He doggedly continued to lobby the spies on Broadway. He sent them missive after conscientious missive, arguing that the realm would be well served in the years ahead if it learned as much as possible about Enigma.
And so, with a behind-the-scenes chorus of sources raising brash voices in unison, with agents already traipsing about Europe on life-and-death missions hoping to discover some clues to the secrets of Enigma, it was inevitable that Jack Shelley, MI6’s man in Warsaw, would be given the assignment too.
Lieutenant-Colonel Colin Gubbins, who as a general would direct the Special Operations Executive (SOE) skullduggery during the war, had come to Warsaw to instruct the Polish general staff about potential sabotage missions if the Germans invaded. His schedule was crammed, rounds of intense meetings followed by the formal dinners his gregarious military hosts insisted upon. Still, Gubbins found a moment to meet with Shelley. As soon as the two men sat down, he announced to the surprised spy that he had brought instructions from London.
Find out, Gubbins said, repeating the words he’d been told, everything the Poles know about Enigma. You are to consider this operation a priority.
The next day Shelley met with his most productive agent. He did not emphasize the significance of what he would ask her to do; in truth, he did not grasp its promise. In his crisp Guardsman’s voice, he simply announced a new mission: Betty should collect all the information she could about the Polish efforts to break the German code.
Canadian William Stephenson, working as an independent asset, during his business trips to Germany, galvanized the efforts of British intelligence to break the Enigma code.
Library of Congress, Prints & Photographs Division, FSA/OWI Collection, LC-USE6-D-oo383-a
IN THE BEDROOM, CUDDLED NEXT to Lubienski, Betty went to work. She did not get everything from the count at once; a lifetime of carefully nurtured instincts had taught her when to prick up her ears and when, with a lighthearted resignation, to allow things to move on. The rule in any honey trap was to tickle, but never to shove. When the target returned to bed, you’d have a second chance. And Betty’s men always hurried back. And back.
Over time Betty filed an impressive series of reports. Many of the secrets she collected remain locked in the Service’s vaults; intelligence agencies stubbornly hang on to even outdated cryptological information. Nevertheless, this much is known:
Working from classified documents that the unsuspecting count routinely brought home each night from Beck’s office, and also blithely guiding their meandering pillow talk, Betty helped the Service monitor the activities of the Black Chamber team. She kept her controllers informed as the young Poles, sequestered in the woods outside Warsaw, received stolen Enigma manuals from the French and struggled to build a prototype. And it was Betty who first reported the startling news that the Poles were able to read Enigma traffic.
“We couldn’t believe our eyes. Here was the missing link in the whole chain of our intelligence on Enigma. . . . And that is where [Betty] came in with the most unexpected results,” one intelligence officer gushed, fulsome in his praise but careful not, even decades later, to reveal too much.
In July 1939, with the war only weeks away, the Poles finally got around to inviting two senior British cryptographers to be briefed on Enigma at their wrangler’s workshop, as the espionage professionals called it, outside Warsaw. The Brits, though, were reluctant to make the trip.
A meeting in January in Paris had been unproductive, the Poles alternatingly testy and tight-lipped. Yet encouraged by Betty’s intelligence, the cipher experts put aside their misgivings and went to Warsaw. It proved to be well worth the effort. Not only did the Poles at last admit that they had broken the Enigma code, but they agreed to ship the British, through an agent in France, a replica of the Enigma machine.
And although she never knew it, it was thanks to her stream of reports on Enigma that Stephenson first heard about Betty. He had continued to offer the Service whatever stray scrap he could get hold of on the machine, but the information she was passing on, according to the confidences whispered to him, was in another league. Hers was, he was told, “vital.”
Betty Pack was clearly an agent, the would-be spymaster told himself, of considerable talent. He made a mental note to remember her name.
THE HOARY PARABLE OF THE blind men and the elephant held, Hyde knew, a special place in the hearts of intelligence agents. From their first days in the secret world, they heard it from trainers and controllers. Just as the blind man could only appreciate the specific part of the elephant that he touched, recruits were lectured time after time, the solitary field agent can never truly understand the total significance of his mission. No single operation, no matter how daring, how costly, how consequential, is more than a small episode in a grand scheme. Intelligence is a communal enterprise.
In an operation as long-running and multifaceted as Enigma it would be a mistake, a sin of naïveté as well as arrogance, to crown a single operative with laurel. Enigma, to use the instructors’ favorite analogy, was an elephant of mammoth and mysterious proportions.
By 1942 the British were decrypting 84,000 German messages each month. As the war raged on, Enigma gave the Allies a formidable advantage; they knew not only the location and strength of the enemy but also their strategy, how they intended to deploy their troops, planes, and ships, and when they planned to attack. As a grateful Dwight D. Eisenhower, commander of the Allied forces, wrote, “It has saved thousands of British and American lives and, in no small way, contributed to the speed with which the enemy was routed and eventually forced to surrender.”