Dr John Watson

Dr John Watson is a main character in the BBC crime drama Sherlock. He is a retired military doctor who left Afganistan after sustaining an injury in his leg. He is Sherlocks best friend and collogue and flat mate. He writes a blog about his adventures with Sherlock and is often mistaken as gay because he spends so much time with Sherlock.

Portrayed by Martin Freeman

History
John Hamish Watson (Martin Freeman) is Sherlock's flatmate and colleague. He is often a foil to Sherlock in both appearance and personality. Unlike Sherlock, John is short with blond hair. He is kind, caring, and 'human' compared to Sherlock's cold, calculating ways. He gets on better with the police and takes care of practical matters at their flat, apparently doing most of the shopping. He also gets a locum job at nearby general practice to help pay the bills, and starts dating Sarah, another doctor he meets working there.

At the start of the series, John was recently invalided home from Afghanistan after serving as an "army doctor" (it is unclear whether John served separately as a doctor then a soldier, or as a medic, although in his first scenes he is shown with a mug with the cap badge of the Royal Army Medical Corps). Prior to his military service, John read medicine at King's College, London as seen on his CV. He is in possession of a pistol, described as a "British Browning L9A1" in the show, but is actually a Sig Sauer P226. John is highly proficient with the weapon, described as a "crack shot" by Sherlock.

Before meeting Sherlock, and after returning to London from Afghanistan, John had several medical issues: a psychosomatic limp in his right leg, and bullet wound in his left shoulder (a reference to the canon), using a cane on his right side. As well, his left hand had an "intermittent tremor". His therapist noted John had "trust issues" and diagnosed him with PTSD, the latter of which Mycroft (Sherlock's brother) later subverted, saying John is not "haunted by the war" but rather misses it for the excitement. Following a chase around London with Sherlock, John's limp disappears (and so, presumably, does the tremor). This only proves the Holmes brothers correct, and John's therapist wrong.

John is also shown to be loyal and courageous, with a strong sense of personal integrity. His "strong moral principles" are likely a result of his medical training and army service. He refuses Mycroft's offer to pay him to spy on Sherlock, despite only having just met Sherlock at this time (and not knowing that Mycroft was his brother). He is willing to occasionally use deadly force, but he is only ever seen to do so when someone else's life is in immediate danger. He shows no visible signs of regretting his actions afterwards.

In the second series, John is referred to as Sherlock's P.A. and is not shown working any other job. John writes about Sherlock's cases on his blog, which attracts clients to them. He also gives the cases names he deems appropriate. Much to John's constant annoyance, he is often mistaken for a gay man because of the time he spends around Sherlock. He is alluded to have had a number of short-lived relationships with women - one of whom is shown ending their relationship due to John's commitment to Sherlock, saying, that "[Sherlock] is a very lucky man."

The only member of John's family that has been alluded to thus far is his sister, Harriet (aka Harry), with whom he has strained relationship as a result of her alcoholism and recent separation from her partner, Clara. During their first case together, Sherlock deduced that John had refused to accept help from Harry after being invalided out of the army, even though the fact that she gave John her old phone was an indication that she wanted to stay in touch with her brother.

Watson's middle name being Hamish was originally proposed by Dorothy L. Sayers to explain discrepancies in Watson's name in the canonical works of Conan Doyle.

Relationships
Sherlock Holmes

Sherlock is Johns best friend. They both work together and live together and have a better relationship then Sherlock has with his brother. Their relationship tends to develop more through out the series and they get along better then they did when they first met and Johns the only one that Sherlock listens to.

Mycroft Holmes

Mycroft tends to annoy John when he unexpectadly brings his private car to John to pick him up to meet him at a secluded place to talk about Sherlock. At first John had no idea who Mycroft was and that he was Sherlocks brother. Mycroft offered John money to keep an eye on Sherlock and to make sure he stays safe.

Jim Moriarty

John hated Jim as much as Sherlock did. Jim tried to blow John up in the season 1 finale. But he has no idea that Sherlock died because of Jim. John shouted at Jim when he was pretending to be an actor Sherlock hired to play Moriarty and never belived Moriarty's storys.

Trivia

 * He was a military doctor in Afganistan
 * He is Sherlocks best friend
 * He lives at 221B Baker Street
 * Moriarty tried to blow him up
 * Mycroft annoys him