Closing credits show some of Sidney Paget's illustrations for the stories originally published in the Strand Magazine.
This show was very much correct on Victorian fashion and Sidney Paget's illustrations on Arthur Conan Doyle's stories. Therefore, Sherlock Holmes is only wearing the trademark deerstalker on several occasions while visiting the countryside, and not even all of them. In episodes set in London, Holmes is more often seen wearing a top hat, although a few episodes show him with a bowler or a homburg.
An engraving of the Reichenbach Falls by William Henry Bartlett hangs above the mantelpiece in Holmes' living room.
Several actors seen in the entire series ("Adventures of / Return of / Case-book of / Memoirs of") also starred in "Poirot" (1989-2013).