The estate of Sir Arthur Conan Doyle, creator of Sherlock Holmes, has filed a lawsuit against the people behind Enola Holmes. The upcoming movie focuses on the sister of Sherlock, played by Stranger Things star Millie Bobby Brown. It was recently picked up by Netflix but now, has become entangled in some legal trouble. The reasoning is a bit baffling though, as the estate alleges that the filmmakers decided to give Sherlock Holmes human feelings.

Conan Doyle's estate filed the lawsuit recently in New Mexico. It names Netflix, Legendary Pictures, Penguin Random House author Nancy Springer, whose novels inspired Enola Holmes. The situation is complicated and has to do with some relatively recent history. The vast majority of the Sherlock Holmes stories went into the public domain back in 2014. This included all of the stories about the famed detective written before 1923. That is key.

RELATED: Enola Holmes 2 Begins Filming Soon, Louis Partridge Returns as Tewkesbury

The lawsuit is attempting to claim that copyright has been infringed with Enola Holmes because the filmmakers have used elements of the books written by Conan Doyle after that period. Specifically, ones in which the author gave the character the ability to feel empathy and respect women, among other things. An excerpt from the filmign reads as follows.

"After the stories that are now in the public domain, and before the Copyrighted Stories, the Great War happened. In World War I Conan Doyle lost his eldest son, Arthur Alleyne Kingsley. Four months later he lost his brother, Brigadier-general Innes Doyle. When Conan Doyle came back to Holmes in the Copyrighted Stories between 1923 and 1927, it was no longer enough that the Holmes character was the most brilliant rational and analytical mind. Holmes needed to be human. The character needed to develop human connection and empathy. 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 a heart. Holmes became warmer. He became capable of friendship. He could express emotion. He began to respect women."

Netflix, Legendary Pictures and the others named in the lawsuit have yet to respond as of this writing. Enola Holmes centers on Sherlock's rebellious teen sister whose mother mysteriously disappears on her 16th birthday. The cast also includes Henry Cavill as Sherlock, with Sam Claflin, Helena Bonham Carter and Burn Gorman rounding out the ensemble. Harry Bradbeer directed the adaptation.

It's worth noting that this isn't the first time the estate has filed such lawsuits. They also went after Miramax for Mr. Holmes in 2015, which was settled to the satisfaction of both parties. Whether or not this lawsuit will ultimately have any effect on the release remains to be seen. The movie was originally set for a theatrical release but those plans were dashed with the ongoing theater shutdown, which resulted in Netflix picking up the rights. No release date has been announced since the streaming service made the deal. This news was previously reported by The Hollywood Reporter.