221A Baker Street

A possible deliberate error by the filmmakers.

I didn't notice that address goof. What I was wondering about was the clue doggerels as the members of the Scarlet Ring were cut down in numbers. I thought surely that's from an Agatha Christie story. But no. This movie predates 'And Then There Were None' which Christie had published in 1939. So it looks as though the mystery author might have cribbed the versed murder clues idea from this film. Some of the verses are very similar and then added to ten in 'And Then There Were None.'