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In 1887, British author Arthur Conan Doyle published “A Study in Scarlet,” a novel featuring a detective named Sherlock Holmes. This wouldn’t be the last Sherlock Holmes mystery — far from it. Doyle would later write three more full novels and dozens of short stories featuring the supremely deductive Holmes, establishing Sherlock as, perhaps, the most famous fictional detective of all time. And Sherlock’s stories didn’t end when Doyle passed away in 1930 — far from it. There have been countless Sherlock Holmes adaptations since.

And in almost all of them, Holmes is a big jerk. That’s not by accident — it was, partially, to avoid a lawsuit.

The mystery starts with a matter of law: copyright, specifically. In the United Kingdom, works typically remain under copyright protection until 70 years after the author dies in the United States, copyright protection for anything published before 1978 runs until 95 years after the first date of publication. Given the dates above, Sherlock Holmes entered the public domain in the UK in 2000. And, as a result, lots of people started creating Sherlock Holmes-inspired stories. Many of them — like Warner Bros. Studios for the movies starring Robert Downey Jr. — still licensed the character from the Doyle estate to mitigate any risk.

The Doyle estate still wanted to monetize Holmes, though, so they looked toward U.S. law. At first, they argued that the fact that Doyle kept publishing Holmes stories through the 1920s should extend the copyright, but the courts didn’t buy it — the 1887 work, for example, entered the public domain in the United States in 2018 (due to various extensions), but only elements from the 1921 story entered in before 2025. Creators could use Sherlock Holmes provided they didn’t take details from the later books.

So there was some risk, but not a lot. But in 2020, the Doyle estate came up with a creative argument: if you used Sherlock Holmes in your stories, he had to be mean. From 1921 to 1927, Doyle published his final twelve stories about Holmes, later collected and shared as a book titled The Case-Book of Sherlock Holmes. And in those Case-Book stories, Holmes is notably different — he comes across as affable, genteel, empathetic, and even warm. He’s simply a more likeable guy. They argued in court filings, via Den of Geek, that starting with those stories, “Conan Doyle made the surprising artistic decision to have his most famous character — known around the world as a brain without a heart — develop into a character with heart. Holmes became warmer. He became capable of friendship. He could express emotion. He began to respect women.” And it was that warmth, caring version of Holmes that the estate asserted was, as of 2020, still their protected IP.

In general, this argument didn’t matter much — small creators would pay a token license to the estate to avoid the risk of litigation, and larger creators tended to make Holmes the cold, calculating character we’re familiar with. But in 2006, author Nancy Springer wrote The Enola Holmes Mysteries, a series of young adult novels about Sherlock’s little sister, Enola. (Enola, to be clear, was entirely a creation of Springer’s.) Sherlock makes some appearances in the books and is a much more vulnerable guy than he is elsewhere, but the Doyle estate didn’t do anything about it — at least, not immediately. But when Netflix decided to turn the Enola Holmes stories into a movie in 2020, the Doyle estate sued, saying that the inclusion of happy Sherlock violated the estate’s rights.

Ultimately, the case was dismissed for reasons unstated — it’s widely believed that Netflix and the Holmes estate settled out of court. But regardless, if you want to write a Sherlock Holmes story where he’s a nice guy, you’re probably in the clear. The 95-year window of protection lapsed a few years ago.

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Today’s Bonus fact: The TV show House, M.D., is an informal Holmes adaptation — Dr. House, like Holmes, is a genius-level detective with awful bedside manner. And the similarities are more explicit than that. The two characters’ last names (say Sherlock’s aloud), per creator David Shore, is “a subtle homage” to Holmes. One has a sidekick named Watson and the other Wilson. And, as seen here, House lives at 221 Baker Street, Apartment B, much like Sherlock.

From the Archives: Agatha Christie’s Unsolved Mystery: This isn’t really about Sherlock Holmes but it does involve Doyle, and I briefly mentioned Holmes, so it counts, right?

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And thanks! — Dan