 The writers say that they did not want to force modernity onto the story . There were some creative challenges , such as the decision to include the sign " 221B " on Holmes ' front door . Gatiss and Moffat reflect that in the modern world the door would only display the number of the house , and there would be doorbells for each flat . The full house number is so iconic that they felt unable to change it . The writers also decided that the lead characters would address each other by their first names , rather than the traditional Holmes and Watson . This was also reflected in the title of the series . Director Paul McGuigan came up with the idea of putting text messages on the screen instead of having cut @-@ away shots of a hand holding the phone . 
