In September 1971, thieves tunnelled into the vault of a bank in London's Baker Street and looted safe deposit boxes of case and jewellery worth millions and millions of pounds. None of it was recovered. Nobody was ever arrested. The robbery made headlines for a few days and then disappeared - the result of a UK government 'D' notice, gagging the press. This film reveals what was hidden in those boxes. The story involves murder, corruption and a sex scandal with links to the royal family - a story in which the thieves were the most innocent people involved.