In 1671, Colonel Blood, an Irish adventurer, presented himself to the keeper of the Tower of London disguised as a country parson. Blood was accompanied by a woman whom he introduced as his wife. During the tour of the Tower, the "wife" fainted and the keeper took them both to his rooms. During the conversation which followed, Blood managed to extract information about the private life of the keeper, Talbot Edwards. He found out that Edwards had an unmarried daughter, and he made up a wealthy nephew who would make a suitable husband for her.

The union was agreed upon and, a few days later, the wedding party arrived at the Tower. Each member of the bridegroom's party had a sword concealed under his coat. While they were waiting for Edward's daughter to appear, someone suggested a visit to the Jewel Room. As soon as the group entered, Talbot was gagged and hit on the head with a mallet.

The thieves did not get far, however. The alarm was raised by Talbot's son and the gang was captured before they had time to escape from the Tower. They still had all of the loot with them.

Surprisingly, Colonel Blood was never punished for the robbery. He insisted on confessing his crime before the king. Charles II, having a similar sense of humour to Blood's, was amused by his stories and his adventurous spirit. Blood was allowed to return unharmed to his estates in Ireland.