John Watson

Dr. John H. Watson M.D. was the literary alias of the assistant to the detective Sherlock Holmes.

Biography
In real life, James studied with Arthur Conan Doyle when they attended the same medical school, (DWM: Prelude to All-Consuming Fire) Edinburgh, ca. 1880. (MA: Evolution)

Watson was known for his fictionalised accounts of the adventures of his friend Sherlock Holmes that were edited by Arthur Conan Doyle, in whose name they were published. Because of this, it was widely believed both contemporaneously and later that Holmes was in fact a fictional character created by Conan Doyle. In 1887, Holmes and Watson assisted the Seventh Doctor in battling the Old One called Azathoth. (NA: All-Consuming Fire)

Later that year, they travelled to 2010 to attend the wedding of Bernice Summerfield and Jason Kane. (NA: Happy Endings)

Fictional / Meta-Fictional Status
On both occasions of their meeting the Doctor and his associates (and during the various references to said meetings) it is suggested that Sherlock Holmes and John Watson are not in fact their real names, but the pseudonyms used in the 'stories'.

Information regarding their encounters with Bernice Summerfield and Ace is only provided in subjective form by Bernice herself and Watson, each of whom maintained diaries of said events. (NA: All-Consuming Fire, Happy Endings)

Behind the scenes

 * Watson is referred to as "James" in the story "The Man with the Twisted Lip". The inference of its use in the Prelude is that Doyle accidentally used his friend's real name.
 * Gareth David-Lloyd played Watson in the 2010 movie Sherlock Holmes.