On the death of Sidney Paget, who had illustrated Conan Dolyle's Sherlock Holmes stories in The Strand magazine, Twidle became one of Doyle's regular artists.
An unlikely encounter with a member of a Sherlock Holmes Society even inspired the artist to paint two portraits of Victorian illustrator Sidney Paget.
It was often compared to the competing publication, Strand Magazine, and many artists, such as illustrator Sidney Paget and author H. G. Wells, sold freelance work to both.
Sidney Poitier | Sidney Lumet | Sidney Nolan | Sidney Bechet | Philip Sidney | Sidney Crosby | Albert Sidney Johnston | Sidney Herbert, 1st Baron Herbert of Lea | Sidney | Paget Parish | Henry Paget, 1st Marquess of Anglesey | Sylvia Sidney | Sidney Reilly | Sidney Altman | Sidney Paget | Sidney Howard | Sidney Colvin | James Paget | Henry Sidney | Walburga, Lady Paget | Sidney Smith | Sidney Lee | Sidney Godolphin, 1st Earl of Godolphin | Sidney Cotton | Sidney Blumenthal | Paget's disease of bone | Donald Sidney-Fryer | William Sidney, 1st Viscount De L'Isle | Sidney Sheldon | Sidney Robertson Cowell |
As the deerstalker is the most typical cap of the period matching both descriptions, it is not surprising that the original illustrations for the stories by Sidney Paget in Great Britain, and Frederic Dorr Steele in the United States, along with other illustrators of the period, depicted Holmes as a "deerstalker man", which then became the popular perception of him.
Doyle also entertained many notable house guests at Undershaw including Sherlock Holmes illustrator Sidney Paget, the famous Sherlock Holmes actor William Gillette and the creator of Dracula, Bram Stoker.