Bio

Mary's past is a little unclear. It is unknown exactly how long John and Mary have been together but they met sometime after Sherlock faked his death. It is possible that they met at the clinic/GPs office where John works as a doctor and Mary works as a nurse. They had been together at least six months before John proposed.

Shortly after they first met Sherlock performed a series of deductions about Mary, which revealed that she was an only child, that she was clever, a nurse, linguist, short sighted, romantic, had a cat, wore size 12, was a disillusioned Liberal Democrat, bakes, had a secret tattoo and an appendix scar, and that she was a "liar". However, Sherlock did not reveal any of these deductions to anyone. Mary Morstan appeared to be a sweet, kind-hearted and lively person. She was very intelligent as she was able to tell when Sherlock was lying and keep the secret of her past from him. She cared a great deal about John and Sherlock.

Her relationship with John was threatened by the discovery that she was once an assassin. She was shown infrequently to be a borderline psychopath. She had an arguably ruthless and violent side, as she was willing to murder Charles Augustus Magnussen in order to keep her secret from John.

She was very intelligent, cunning and calculating, a tactical adept. She was also an excellent markswoman, a crack shot with small handguns, showing reflexes and perfect timing, able to shoot a hole in a fifty-pence coin, but failing to hit the centre. She also had a photographic and extensive memory.