Which Sherlock episode is based on Arthur Conan Doyle’s “The Dying Detective”?

“The Lying Detective” is the Sherlock episode based on Arthur Conan Doyle’s “The Dying Detective.”

The episode is the second instalment of Sherlock’s fourth series and was broadcast in 2017. Its story follows Sherlock as he investigates the powerful businessman Culverton Smith, who is suspected of being a serial killer. Sherlock also deliberately creates the appearance that he is seriously ill, echoing the deception used by Holmes in Doyle’s original story.

The television adaptation changes the setting, characters and details to fit the modern series. John Watson is dealing with grief and personal turmoil, while Sherlock’s investigation becomes entangled with the Holmes family and the consequences of earlier events. Toby Jones plays Culverton Smith.

The title is a deliberate variation on Doyle’s title rather than a direct repetition. “The Lying Detective” should not be confused with “His Last Vow,” another Sherlock episode built around a major literary adaptation and a dangerous antagonist.