Harry Houghton traded Admiralty secrets to the Soviets for ten years

By Constance Bell · August 17, 2026

British naval secrets were leaked from 1951 until a 1961 arrest, leaving the Admiralty’s underwater detection capabilities exposed to the Soviet Union.

The British Admiralty spent a decade operating under the assumption that its underwater detection secrets were secure, while a clerk in their own midst ensured they were not. This betrayal compromised the silent war beneath the waves, handing the Soviet Union a window into how the West tracked submarines.

According to the public record, Harry Frederick Houghton was a British Naval Senior Non-Commissioned Officer and a member of the Portland spy ring. But the clinical nature of the archival records provides a tighter timeline of the breach. The file's catalogue entry records that Houghton was a Soviet spy convicted of espionage in 1961, and that "all the indications are that he had been a spy from 1951 until his arrest."

A Clerk at Portland

In the hierarchy of intelligence, the most damaging leaks rarely come from the generals; they come from the people who file the papers. The catalogue description for file KV 2/4381 identifies Houghton as a clerk in the Admiralty Underwater Detection Establishment at Portland. It was from this vantage point that he could access technical data that the Soviet Union desperately needed to evade Western sonar and acoustic detection.

He did not act alone. The archive description notes that Houghton "conspired with another employee Ethel Gee to pass classified material to the Soviet Union." While the catalogue provides no details on the specific nature of Gee's role or the exact volume of the documents they passed, the partnership indicates a vulnerability within the Establishment's internal security. Two employees, working in tandem, were able to operate for ten years without detection.

Ten Years of Leaks

Ten years is an eternity in the context of Cold War technological competition. Between 1951 and 1961, the transition from early post-war sonar to more sophisticated underwater detection was critical for NATO's ability to monitor Soviet submarine movements in the Atlantic. The catalogue entry for KV 2/4482 emphasizes the duration of the breach, noting that the spying lasted from 1951 until the moment of arrest.

Because these records are catalogue descriptions rather than the full case files, the precise nature of the "classified material" remains unspecified. We do not know which specific sonar frequencies were compromised or which detection methods were rendered obsolete by Houghton's transmissions. We only know the duration of the leak and the eventual conviction.

Other Agents in the Series

Finding Houghton's name in the Security Service's "Personal (PF Series) Files" places him in a wider ledger of betrayal. These files, specifically categorized as "SOVIET INTELLIGENCE AGENTS AND SUSPECTED AGENTS," show that the Houghton-Gee ring was part of a broader Soviet effort to penetrate Western military and scientific projects.

Other entries in the same series illustrate the scope of the target list. Catalogue reference KV 2/3788 describes Arthur Alexandrovitch Adams as "one of the most important Soviet espionage agents known to have operated in North America," tasked with penetrating the US atomic bomb project in the 1940s. Another entry, KV 2/1405, records the activities of Gerda Maria Frankfurter, a support agent for Soviet networks in Paris and the United States during the 1930s.

When viewed alongside these cases, Houghton's decade at Portland looks less like an isolated lapse in judgment and more like a successful application of the NKVD and Smersh methods. A captured German document from 1943, listed as KV 5/23, describes the organization and methods of these Soviet counter-espionage services, highlighting a long-standing institutional capability for embedding agents in sensitive positions.

There are multiple entries for Houghton in the National Archives, including KV 2/4477, which specifically notes the inclusion of a photograph. Other related files, such as CSC 11/136 and KV 2/4385, exist in the UK National Archives, though their full contents are not detailed in the catalogue descriptions.

The record leaves us with the image of a naval clerk and a colleague quietly stripping the Admiralty of its underwater advantages for a decade. Whether the Soviets completely mapped the British detection capabilities during those ten years remains an open question.