In the 70’s there was a TV series called “The Rivals of Sherlock Holmes”. The episodes featured detectives that were contemporaries of Sherlock Holmes. Some of the short stories are in Public Domain, that’s why I can give you the links to those stories.
I’m considering the copyright in Europe, death + 70 years. This means that not all stories are in public domain in Europe.
Some of the titles are in Public Domain in USA, because they were published before 1923, others are in Public Domain in Canada and Australia because the copyright there is death + 50 years, but not in Portugal/Europe. So if you are in USA or your country has a copyright that is less than the copyright in Europe you’ll be able to find them on websites like Gutenberg, Gutenberg Australia or MobileRead.
At the end, I’ll give you a link to Archive.org with the stories in AudioBook format.
The list (adapted from Wikipedia) gives the title of the story with link (if in public domain) + detective + author with link to Wikipedia.
If you detect errors, I’ll be happy to correct them.
- Episode 1 – A Message from the Deep Sea (Dr. Thorndyke – R. Austin Freeman)
- Episode 2 – The Missing Witness Sensation (Max Carrados – Ernest Bramah)
- Episode 3 – The Affair of the Avalanche Bicycle & Tyre Co. Ltd. (Horace Dorrington – Arthur Morrison)
- Episode 4 – The Duchess of Wiltshire’s Diamonds (Simon Carne – Guy Boothby)
- Episode 5 – The Horse of the Invisible (Carnacki – William Hope Hodgson)
- Episode 6 – The Case of the Mirror of Portugal (Horace Dorrington – Arthur Morrison)
- Episode 7 – Madame Sara (Dixon Druce)
- Episode 8 – The Case of the Dixon Torpedo (Martin Hewitt – Arthur Morrison)
- Episode 9 – The Woman in the Big Hat (Lady Molly – Baroness Emma Orczy)
- Episode 10 – The Affair of the Tortoise (Martin Hewitt – Arthur Morrison)
- Episode 11 – The Assyrian Rejuvenator (Romney Pringle – Clifford Ashdown, nom de plume of R. Austin Freeman)
- Episode 12 – The Ripening Rubies (Bernard Sutton – Max Pemberton)
- Episode 13 – The Case of Laker, Absconded (Martin Hewitt – Arthur Morrison)
- Episode 1 – The Mysterious Death on the Underground Railway (Polly Burton – Baroness Emma Orczy)
- Episode 2 – Five Hundred Carats (Inspector Lipinzki – George Griffith)
- Episode 3 – Cell 13 (Professor Van Dusen – Jacques Futrelle)
- Episode 4 – The Secret of the Magnifique (John Laxworthy – E. Phillips Oppenheim)
- Episode 5 – The Absent-Minded Coterie (Eugene Valmont – Robert Barr)
- Episode 6 – The Sensible Action of Lieutenant Holst [The original book is Danish. Couldn’t find an English translation in public domain]
- Episode 7 – The Superfluous Finger (Professor Van Dusen – Jacques Futrelle)
- Episode 8 – Anonymous Letters (Dagobert Trostler) [The original book is in German. Couldn’t find an English translation in Public Domain]
- Episode 9 – The Moabite Cypher (Dr. Thorndyke – R. Austin Freeman)
- Episode 10 – The Secret of the Fox Hunter (Duckworth [William] Drew – William Le Queux)
- Episode 11 – The Looting of the Specie Room (Mr. Horrocks – C. J. Cutcliffe Hyne)
- Episode 12 – The Mystery of the Amber Beads (Hagar – Fergus Hume)
- Episode 13 – The Missing QCs (Charles Dallas – William Arthur Dunkerley) [Couldn’t find the story in text format]