Unique footage of MI6 communication staff at Bletchley Park during World War Two has been discovered.
The silent film, which shows men and women while off duty, was donated in its original canister by a donor who wishes to remain anonymous to the Bletchley Park Trust.
It is the only known footage of Whaddon Hall, a secret site connected to Bletchley Park, from the Second World War.
"We don’t know who filmed it and the footage doesn’t gives away any state secrets or any clues about the work the people in it are doing," Dr David Kenyon, Research Historian at Bletchley Park said.
"It is an astonishing discovery and important record of one of the most secret and valuable aspects of Bletchley Park’s work," he added.
During the Second World War, Whaddon Hall was an extremely secret site and all photography and filming were banned.
Ultra intelligence, a classification given to intelligence produced by the Government Code and Cypher School (CG&CS) at Bletchley Park such as Enigma, would be sent to Whaddon Hall and then passed on to Allied commanders in the field.
The footage shows a compilation of moving pictures shot between 1939 and 1945.
"Not only does it show us the place and the people in wartime but it’s the first piece of film footage we’re aware of that shows any of the activity associated with Bletchley Park at all," Perolen Craddock, Head of Collections and Exhibitions at Bletchley Park said.
A number of members of MI6 Section VII stationed in Buckinghamshire are featured in the silent clips.
Second World War veteran Geoffrey Pidgeon, who started working for MI6 Section VIII at just 17 years of age, helped authenticate the footage.
Mr Pidgeon's father, Horace 'Pidge' Pidgeon, worked at Whaddon Hall from July 1940 until December 1945.
Horace managed MI6 wireless stores and provided radio equipment for agents in the field.
He is one of the people featured in the unique footage.
"I'd never seen my father on a cinefilm before," Mr Pidgeon, who called the film "a remarkable find", said.
"I was very surprised and moved to watch it for the first time."
While most of the footage is shot in black and white, part of the film also shows colour footage of men and women off duty at Whaddon Hall and at Whaddon Chase.
A football game and a cricket match during summertime are also featured.
Other than Horace 'Pidge' Pigeon, some of the people appearing in the film have been identified as Brigadier Richard Gambier-Parry, who was the Head of the SIS Section VII, and Bob Hornby, First Engineer who was in charge of workshops, as well as Eward Holden, Stores Officer.
Several other figures featured in the footage have yet to be identified.
The Bletchley Park Trust is appealing to anyone who recognises someone in the film to get in touch.
The film will be preserved as part of Bletchley Park’s collections, and made accessible for research, when the museum and heritage attraction reopens.
Cover image: Part of the footage shows men working for MI6 during the Second World War at Whaddon Hall (Picture: Bletchley Park/YouTube).