Harry Houghton Sold Admiralty Underwater Secrets to Moscow Until 1961

By Harlan Pryce · August 19, 2026

For ten years, a naval clerk and his accomplice leaked classified military data to Soviet intelligence, a betrayal detailed in the Security Service's PF series files.

British naval security was gutted from within by a clerk who traded underwater detection secrets for Soviet favor. For a decade, the silence of the depths was compromised, leaving Western fleets vulnerable to a Soviet Union eager for the edge.

In the quiet coastal stretch of Portland, the Admiralty Underwater Detection Establishment was tasked with the technical invisibility of the Royal Navy. It was a place of precise measurements and high-stakes acoustics. Yet, as the archives now show, the security of the site was a fiction. Harry Frederick Houghton, a British Naval Senior Non-Commissioned Officer, operated there not as a guardian of secrets, but as a conduit for them.

Portland and the Admiralty

The file's catalogue entry for KV 2/4381 records that Houghton served as a clerk within the Admiralty Underwater Detection Establishment. In the hierarchy of military intelligence, a clerk is often overlooked—a ghost in the machine who handles the paperwork without being seen as the primary target of counter-intelligence. This invisibility was Houghton's greatest asset.

The catalogue descriptions for several files—including KV 2/4381, KV 2/4384, and KV 2/4385—confirm that Houghton did not act alone. He conspired with another employee, Ethel Gee, to pass classified material to the Soviet Union. This was not a momentary lapse in judgment or a single act of desperation; it was a sustained operation. According to the consensus of opinion recorded in the Security Service's PF series files, Houghton had been a spy from 1951 until the moment of his arrest.

For ten years, the two employees worked in tandem, turning a specialized naval facility into a Soviet intelligence outpost. The nature of the material they passed is not detailed in these catalogue summaries, but the location—the Underwater Detection Establishment—suggests a focus on the most sensitive aspect of Cold War naval warfare: the ability to find, and not be found by, submarines.

Ethel Gee

The mention of Ethel Gee in the records adds a layer of interpersonal risk to the operation. Espionage is rarely a solo venture; it requires a network of trust, and in the case of the Portland spy ring, that trust was shared between colleagues. The catalogue entry for KV 2/4381 explicitly links her to the conspiracy, framing their partnership as the engine of the leak.

When two people within the same office are compromised, the risk of detection increases, but the volume of available data grows. Together, Houghton and Gee could monitor different streams of information, ensuring that the Soviet Union received a comprehensive picture of British underwater capabilities. The Security Service files, specifically those categorized under "Soviet Intelligence Agents and Suspected Agents," treat their cooperation as a central fact of the breach.

Warsaw and the Embassy

Betrayal rarely begins in a vacuum. The catalogue descriptions for KV 2/4381 and KV 2/4385 provide a critical biographical detail: before his time at Portland, Houghton had worked at the British Embassy in Warsaw.

For an analyst, this is the most telling piece of the puzzle. Warsaw was a city under the heavy thumb of the Polish People's Republic, a primary satellite of Moscow. It was a place where the Soviet intelligence apparatus was omnipresent and highly skilled at identifying vulnerable targets within foreign embassies. The public record confirms that Houghton was a spy for both the Soviet Union and the Polish People's Republic, suggesting that his recruitment likely occurred during his posting in Poland.

By the time he reached the Admiralty in Portland, Houghton was already a conditioned asset. He was not a recruit who had been swayed by ideology in the English countryside, but a professional who had been cultivated in the heart of the Eastern Bloc. The transition from an embassy clerk in Warsaw to a naval clerk in Portland allowed him to move from diplomatic intelligence to technical military secrets without triggering the alarms of his superiors.

Conviction in 1961

The archival trail ends with the collapse of the operation. The catalogue entries for KV 2/4476 and KV 2/4478 are blunt: Harry Frederick Houghton was a Soviet spy convicted of espionage in 1961.

These files sit alongside other high-profile breaches of the era. For instance, the catalogue description for KV 2/3788 details the activities of Arthur Alexandrovitch Adams, whom the Security Service described as one of the most important Soviet agents known to have operated in North America. The juxtaposition of these files in the same archival series illustrates the scale of the Soviet effort: while Adams targeted the atomic bomb project in the United States, Houghton was methodically draining the technical secrets of the British Navy.

The Security Service's files on Houghton are fragmented across multiple references—KV 2/4381, 4384, 4385, 4476, and 4478—each repeating the basic facts of his conviction and his ten-year tenure as a mole. This repetition reflects the way the bureaucracy of intelligence archives the fallen: a series of redundant markers for a man who spent a decade making himself invisible.

What remains unanswered in these summaries is the full extent of the damage. While the files record that he passed "classified material," the specific documents that left Portland for Moscow remain a gap in the catalogue description. The record tells us who betrayed the secret, but it does not tell us exactly which secrets were lost.