Sherlock: 10 Most Outrageous Fan Theories

8. Sherlock Was An MI6 Agent

Over the three Sherlock series we have gathered vague hints about the backstory of Sherlock and Mycroft's fractured relationship and this seemingly crazy theory offers a possible explanation for their problems - Sherlock was actually a secret agent! The name's Holmes. Sherlock Holmes.

According to the theory, Mycroft - as is heavily hinted during the series - is the head of the British secret service (like M in James Bond, geddit?) and at some point in the past hired his brother as one of his agents. It then states that the alluded to third Holmes brother was also an agent but met some terrible fate on the field. This trauma caused Sherlock to quit the job and become a private detective, and brought about the rift between the two remaining brothers.

And speaking of the third Holmes brother...