Donald Maclean Used Five Aliases to Mask Soviet Spying in Washington

By Harlan Pryce · August 18, 2026

He spent decades in the heart of the British Foreign Office feeding secrets to Moscow before vanishing into the USSR with Guy Burgess in 1951.

High-ranking diplomats trusted with the most sensitive secrets of the Western alliance found their communications exposed to the Kremlin for two decades. The cost was a systemic compromise of the British Foreign Office and a breach of trust that reached the highest levels of the Washington Embassy.

The file's catalogue entry records the career of Donald Duart Maclean, a "high flying employee of the Foreign Office" who operated as a Soviet agent from the 1930s until his disappearance. For years, Maclean navigated the corridors of power in Paris, London, and Washington, D.C., eventually rising to head the American Department in the Foreign Office, according to the public record. He was a man of immense trust and even greater betrayal.

Richard Curzon and the Other Men

Tradecraft is often a matter of identity management. According to the catalogue description for file KV 2/4151, Maclean did not operate under his own name alone. He utilized a series of aliases—Richard Curzon, Mark Frazer, Percy Maclean, and S Madzoevsky—to shield his activities from his colleagues and the security services. When a man in the Foreign Office carries four different names, he is not merely avoiding a paper trail; he is building a wall between his public service and his private loyalty to a foreign power.

His wife, Melinda Goodlett Maclean, was similarly entwined in the deception. The record lists her as an American and British national, operating under aliases including Melinda Marling, Melinda Philby, and Natasha Frazer. In the clandestine service, the spouse is often either the most vital asset or the most dangerous liability. In this case, the marriage served as another layer of cover for a partnership in treason.

1951: Flight to Moscow

The facade collapsed in 1951. The catalogue entry notes that by that year, Maclean was "identified as the source of a leakage from the Washington Embassy some years earlier." The timeline is the most damning part of the record. Maclean had been assessed as a Soviet agent since the 1930s, meaning he spent the majority of the Second World War and the critical opening years of the Cold War delivering the West's inner thoughts to Moscow.

While under investigation, Maclean did not wait for the handcuffs. He fled to the USSR alongside Guy Burgess. The public record identifies them both as members of the Cambridge Five, a ring of spies recruited from the university's elite. These men did not spy for money; they spied for an ideology that demanded the betrayal of their own government and their own class. They viewed their treason as a higher form of loyalty, a delusion that allowed them to walk the halls of the Foreign Office while reporting to the NKVD.

Security Service Records

The National Archives' KV 2 series reveals a broader, more desperate effort by the Security Service to map the Soviet network. Maclean's file sits among a collection of "Soviet intelligence agents and suspected agents," acting as a focal point for a wider pattern of infiltration.

Related records show the Security Service casting a wide net, often catching the smaller fish while the sharks swam overhead. File KV 2/4516 details the movements of Victor Nicolaevich Antonov, a Tass correspondent in Sydney whose reports to Moscow covered atomic tests and political trends. File KV 2/3786 describes Philip Rosenbliett, an American dentist who was named as an agent by the defector Krivitsky in 1939. Even the movements of Ian Frank George Milner, a New Zealander in the United Nations Secretariat, were logged under KV 2/4371 due to "communist associations in his university days."

The Security Service was not merely tracking individuals; they were attempting to formalize the process of betrayal. File KV 4/334 describes the "procedure for bringing to the UK alien defectors from Russian Intelligence Services," suggesting a standardized method for harvesting the secrets of those who finally turned against Moscow.

Yet, for all the procedures and the meticulous files on Tass correspondents and dentists, the high-flying diplomat in the Foreign Office remained undetected for nearly twenty years. The record indicates that Maclean's betrayal was only confirmed after the damage to the Washington Embassy had already been done. The security apparatus failed not because it lacked files, but because it failed to look closely at the men it trusted most.

The file's catalogue entry does not specify the exact nature of the "leakage" from the Washington Embassy that finally exposed Maclean.