In September 1971, thieves tunneled into the vault of a bank in London's Baker Street and looted safe deposit boxes of cash and jewelry worth over three million 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 'D' Notice, gagging the press. This film reveals what was hidden for the first time. 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.