Crime and Scandal

Lona Cohen – The Spy Who Kept Her Cool Even in the Desert

The year was 1945 and 32-year-old Lona Cohen from Adams, Mass., was in the New Mexico desert. Americans had perfected the nuclear bomb and used it to end World War II. In the Los Alamos desert the security around the nuclear labs was intense. The Soviet Union desperately wanted to build their own nuclear weapons, and Communists had persuaded a young physicist, Theodore Hall, to smuggle secrets from the lab and deliver them to the Soviets.

Hall handed off a trove of documents to a crafty courier, Lona Cohen, and she immediately boarded a train to New York. From there her contacts could get the documents to Russia. Lona was stunned to see military police board the train and begin searching passenger belongings. Cool and polished as ever, Lona folded the secret documents into her newspaper.

When police arrived at her seat, she asked the soldier if he would mind holding her newspaper while she opened her bags for him. He happily complied and returned the newspaper when he had verified that Cohen didn’t smuggle any nuclear secrets in her bags.

The Legend of Lona Cohen

Lona Cohen became a legend in the Soviet KGB that day. And the Soviets would develop their first nuclear bomb based on the plans she carried out of Los Alamos that day.

So how did a small-town girl from Adams, Mass., get to become a Soviet spy funneling state secrets from West to East for more than 25 years? Historians don’t know the details.

Lona was born Leontine Petka in 1913 in Adams into a large Polish Catholic family. Her father worked in a cotton mill. The family moved to Taftville, Conn., in 1923, and at 15 Lona left home to move to New York City.

Lona had a front row seat to watch the collapse of the economy and the misery brought on by the Great Depression. Disenchanted with America’s ruling elite, she joined the Communist Party and married Morris Cohen, who fashioned himself a Communist intellectual.

Morris Cohen

As early as 1938 Morris affiliated with Russian intelligence, eavesdropping and couriering information to Russia. In 1940, Morris was drafted to serve in World War II. Lona took on more responsibility, which led to her dramatic trip to Los Alamos.

Cold War

As the Cold War heated up, so did the search for Russian spies. The Morrises knew Ethel and Julius Rosenberg, and their arrest in 1951 shook them. Panicked by news that the FBI was on to them, but clever as always, Morris and Lona escaped detection. The Soviets brought them to Mexico and then Russia.

In Russia, the Soviets developed new identities for Lona and Morris. They became Peter and Helen Kroger – antiquarian bookdealers from New Zealand who had resettled in London. In London, they became central players in a spy ring operating in England for seven years. They had a secret radio tower built in their house, which they used to relay messages to Russia.

The “Kroger” house in London

While in England, the Morris’ belonged to the Portland Spy Ring, sending British naval secrets to Russia. The leader of the ring drew suspicion on himself with lavish spending and drunkenness. The Morris/Krogers, meanwhile, were not exactly discreet.

In her book The Duchess of Bloomsbury Street, author Helene Hanff told the story of how the couple was nearly outed at a New Year’s Eve party by their host. She remarked on Lona/Helen’s exquisite black dress: “‘Helen, you look like a Russian spy!’ she said. And Helen laughed and Peter laughed and a few months later we picked up the morning paper and discovered that Helen and Peter Kruger were Russian spies.”

Lona tried one last clever move as police raided her home. Could she, she asked, stoke the boiler to keep the house warm before leaving with police? This time her captors were a step ahead of her. They followed her to the basement and stopped her from tossing secret stolen documents into the furnace.


In 1961, Lona and Morris were convicted and sent to prison. After eight years, the British exchanged them for a British citizen imprisoned in Russia. The KGB gave them a hero’s welcome.

Lona and Morris Cohen, just released from prison.

Lona died in 1992 and Morris in 1995. He received a hero’s funeral. Despite their arrest, the two had kept their secrets.

The identity of Theodore Hall, the physicist who handed those atomic secrets to Lona in the desert all those years ago, was not revealed until after Lona and Morris had died – long after the collapse of the Soviet Union. The Soviets decorated Lona with the Honor of The Red Banner and the Order of Friendship Peoples. The Russian government issued a commemorative postage stamp bearing her likeness.

This story was updated in 2021.

Images: Cohens’ home in London By Russell Trebor, CC BY-SA 2.0,

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