The MI5 Archive – Official Secrets
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MI5 Official Secrets
📅 Friday, November 27, 2026
🇺🇸 6:00 AM – 7:00 AM PDT
🇬🇧 The UK National Archives
Vimeo | Virtual Online Event
🕵️ The MI5 Archive: Official Secrets • Online National Archives Talk
Explore more than a century of British security-service history through MI5 files preserved at The National Archives.
Step inside the secretive history of Britain’s domestic security service during The MI5 Archive: Official Secrets, a free online talk presented by The National Archives. The program explores MI5 from its origins through the modern era using the extensive collection of security-service records that have gradually entered the public archive.
For much of its history, MI5 operated almost entirely in secret, but beginning in the 1990s the service began releasing historical files to The National Archives. Those records now provide researchers and the public with an extraordinary documentary trail covering espionage, subversion, intelligence investigations, and national-security history.
National Archives contemporary specialist Mark Dunton, co-author with archivist Stephen Twigge of The MI5 Archive: Official Secrets, will discuss how the book developed and share some of the stories uncovered within the MI5 records held by the archive.
🗄️ Inside the MI5 Archive
▫️ Origins of Britain’s Security Service
▫️ Historical MI5 files
▫️ Espionage & subversion
▫️ Intelligence investigations
▫️ Declassified archival records
▫️ Stories uncovered by researchers
📅 Event Details
▫️ Date: Friday, November 27, 2026
▫️ Time: 14:00–15:00 UK time
▫️ Time: 6:00–7:00 PST
▫️ Platform: Vimeo livestream
▫️ Price: Free / pay what you can
▫️ Presenter: The National Archives
🎤 Featured Speaker: Mark Dunton
Mark Dunton is a contemporary specialist at The National Archives and co-author of The MI5 Archive: Official Secrets with archivist Stephen Twigge. During the program, Dunton will discuss the creation of the book and highlight stories of subversion and espionage preserved within the MI5 collection.
ⓘ Online Event: This program is presented online and livestreamed through Vimeo. The National Archives lists the program for 14:00–15:00 UK time. Viewers outside the United Kingdom should confirm the corresponding local time before joining.
ⓘ Event Information:
The MI5 Archive: Official Secrets is presented online by The National Archives on November 27, 2026.
The live program runs from 14:00–15:00 UK time.
The event is listed as free with a pay-what-you-can option. Check the official National Archives event page for registration, livestream access, and any schedule updates.