NEW YORK (NYT NEWS SERVICE).- Like a home movie reel, the silent footage shows young people at candid moments: playing soccer and cricket, sunbathing, smiling and making faces at the camera.

Subtitles capture some of what they say: “What … what time is our party?” one man asks.

But they were not ordinary office colleagues: They were off-duty secret British communications staffers, linked to code-breakers who decrypted German ciphers and helped the Allies win World War II.

The newly revealed footage features staff members of the MI6 Section VIII — the British spy agency’s communications staff — filmed at a site associated with the famous code-breaking facility Bletchley Park.

The video, believed to be a compilation of footage recorded between 1939 and 1945, was filmed at Whaddon Hall in Buckinghamshire, England, the secret site where intelligence produced by the code-breakers would be sent and then shared with Allied commanders in the field, according to Bletchley Park, which is now a heritage site and museum. It released and published some of the footage online on Friday.

“No other film footage of a site intimately connected with Bletchley Park exists,” David Kenyon, research historian at Bletchley Park, said in a statement.

Bletchley Park does not know who recorded the footage, he said. The reel was presented in its original film canister and given by an anonymous donor in the second half of 2019.

The footage does not reveal sensitive information about the work the staff performed at the time, Kenyon said. “If it fell into the wrong hands, it would have given little away,” he said. “But for us today, it is an astonishing discovery and important record of one of the most secret and valuable aspects of Bletchley Park’s work.”

Peronel Craddock, the head of collections and exhibitions at Bletchley Park, said in an interview that the footage was a remarkable window into “what it was like to work as part of the Bletchley Park operation in wartime.”

“These young people were doing extraordinary work under conditions of complete secrecy,” she said. “We know of the vital importance of their work from official records, but the film gives a rare glimpse into the lighter side of their wartime life — playing sport, enjoying the outdoors and joking around with friends.”

During World War II, Bletchley Park, a sprawling estate north of London, was the home of British code-breaking, and where the British mathematician and computer pioneer Alan Turing oversaw a staff of specialists to decrypt ciphers generated by Nazi Germany’s Enigma machine.

For years, German submarines hunted Allied vessels in the Atlantic, disrupting convoys carrying vital supplies, and the cryptologists of Bletchley Park were critical in decoding messages that charted the subs. With that knowledge, Allied ships could alter their courses, keeping Britain supplied and preparing for the Allied invasion of D-Day.

Whaddon Hall, about 6 miles west of Bletchley Park, was used by MI6 during the war and is now private housing.

“The Whaddon Hall film is a really significant addition to our collection,” Craddock added in the statement. She said that researchers at Bletchley Park had spent some time researching the places and individuals in the footage before releasing it.

To help validate the footage, Bletchley Park officials said, they showed it to Geoffrey Pidgeon, a World War II veteran who worked for the MI6 section when he was 17. The footage captured his father, Horace “Pidge” Pidgeon, who also worked at Whaddon Hall, providing radio equipment for agents in the field.

Others identified in the film include Bob Hornby, an engineer, and Ewart Holden, a stores officer, Bletchley Park said. But several others in the film have not been identified, and the museum is asking the public for help in doing so.

The facility has been temporarily closed since March 19 because of the coronavirus pandemic, but said in its statement that the footage would join the facility’s collections and be accessible for research when it reopens.

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