THE ALLEGED THEFT OF ALL THE DOCUMENTS
The first stage of the operation consisted in stealing documents of the collection from the Duke's home to prevent any possible claims by the owners of the pictures that were about to be stolen. So, on the night of 23 February 1977, two persons posing as servants, hired two months previously, set about stealing the documents after drugging the rest of the staff. The fake servants left the house with the property deeds of the works along with 17 pictures from the collection and set off for Portugal.
Nine days later, The Royal Household, filtered the news of the robbery to the press via the police. On March 2nd 1977, the news was published in Spain, concentrating on the theft of the pictures, with no mention of the documents. Two months later, the pictures turned up in Portugal and the thieves were arrested, but with no mention of the documents stolen.
In 1979, the Duke of Hernani's family discovered that criminal proceedings had never been instigated for this robbery. It was all a set-up and nothing more was heard of the fake servants.
FALSIFYING THE WILLS
The old Duke of Hernani died on January 6th 1979 at the age of 91, and the Royal family allegedly got hold of the pictures, some of which were deposited in the Prado Museum.
In order not to give rise to suspicion, they falsified the Duke's last will, placing his second wife, Teresa Mariategui Arteaga as the only heir, but acting as a symbolic heir or figurehead who would then hand over the pictures. At the same time, in order to justify the later appearance of the pictures in the Royal family's private estate, the king granted a Royal Decree allowing the Duchy of Hernani to be held by his family, to be exact by his sister Margarita, under the alleged pretext that he had received a letter from the Duke expressing his wish to change the Duchy's line of succession through the will. This letter, was again allegedly a forgery.