The producers of Netflix’s hit mystery filmEnola Holmes,which starsStranger Things’s Millie Bobby Brownas Sherlock’s little sister,are fighting back against a copyright lawsuit from the estate ofSherlock Holmescreator Sir Arthur Conan Doyle. In a motion to dismiss, their lawyers argue that the suit itself is an attempt “to use trademark law to do what copyright law can no longer do: prevent others from freely using and adapting Sherlock Holmes in their own works.”

Conan Doyle Estate Ltd, a company run by Doyle’s indirect descendants,filed suit in Juneagainst Netflix, Legendary Pictures, director Harry Bradbeer, screenwriter Jack Thorne, andEnola Holmes Mysteriesauthor Nancy Springer. It alleges copyright infringement and violation of trademark. The defendants, in turn, filed motion to dismiss in New Mexico, where the original lawsuit was filed, on October 30th.

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The fact that the Doyle heirs can file a lawsuit here at all is due to a quirk in U.S. copyright law. In the United Kingdom, works remain in copyright for 70 years following the death of their original author. Arthur Conan Doyle died in 1930, of a heart attack at his home in East Sussex, so in the UK, Sherlock Holmesand all related conceptshave been public domain for 20 years. The end.

However, in the United States, copyright applies to individual works, and lasts for 95 years following the date of the work’s first publication, regardless of the continued existence of its creator. (This has infamously been changed several times as part of an ongoing attempt by Disney to keep Mickey Mouse out of the public domain.) As such, there are a handful of Sherlock Holmes short stories that Doyle wrote in the late 1920s, such as “The Adventure of the Three Gables,” that arestill covered by copyright.

The Doyle estate’s lawsuit againstEnola Holmeshinges on those final short stories, the last of which will enter the public domain in 2023. Those stories, originally collected in 1927’sThe Case-Book of Sherlock Holmes, depict a more emotional, humanized Sherlock than most of the previous canon. The lawsuit claims that this this is due to Doyle having lost both his eldest son and his brotherin World War I. When he started writing Sherlock Holmes stories again a few years later, his grief led to him developing Sherlock into a warmer, more empathetic character.

Therefore, sinceHenry Cavill does not play Sherlock Holmes as an emotionless robotinEnola Holmes, the suit claims that the depiction infringes upon the Doyle estate’s copyright, which still barely applies in the United States to several of those final short stories.

The lawyers for the defense do not consider this a compelling argument. Attorney Nicolas Jampol, a partner at Davis Wright Tremaine, writes, “Copyright law does not allow the ownership of generic concepts like warmth, kindness, empathy, or respect, even as expressed by a public domain character.” In other words, Netflix and company’s defense here is thatLogical Jerk Sherlock Holmesand Surprisingly Nice Sherlock Holmes arestill the same character, and are not legally distinct enough that one is copyrighted while the other obviously isn’t.

TheEnola Holmeslawsuit does form part of an unfortunate pattern by Doyle’s estate. This is the third lawsuit since 2014 that Doyle Estate Ltd. has filed over licensing rights to Sherlock Holmes, following a loss in court against anthology editor Leslie Klinger (In the Company of Sherlock Holmes) and an out-of-court settlement with Miramax over the 2015 filmMr. Holmes,which features Ian McKellenas a 93-year-old retired Sherlock. Notably, theMr. Holmessuit names the same complaints as the one againstEnola Holmes,with the Doyle estate alleging infringement upon the details from Doyle’s last published, still-copyrighted short stories.

Doyle has no living direct descendants after his daughter Jean’s death in 1997, but a number of surviving grand-nieces and -nephews operate Conan Doyle Estate Ltd. Through that company, the Doyles still collect licensing feesfrom recent Holmes adaptations, such asSherlockandElementary. From the outside, it looks an awful lot like the Doyles see the end is coming for their century-long meal ticket, and are trying to file as many nuisance lawsuits as possible in the meantime.

The last of Arthur Conan Doyle’s original Sherlock Holmes stories, “The Adventure of Shoscombe Old Place,” will enter the public domain on June 07, 2025.