 The update maintains some traditional elements of the stories , such as the Baker Street address and Holmes 's adversary Moriarty . Although the events of the books are transferred to the present day , some elements are incorporated into the story . For example , Martin Freeman 's Watson has returned from military service in Afghanistan . While discussing the fact that the original Watson was invalided home after serving in the Second Anglo @-@ Afghan War ( 1878 – 80 ) , Gatiss realised that " [ i ] t is the same war now , I thought . The same unwinnable war . " 
