The creators of Sherlock have pleaded with fans not to share a leaked final episode of the current series that has appeared online.
Images apparently taken from what is reportedly a Russian version of the final episode have been circulating on social media.
A tweet on the show's official page said the producers had become aware that the final episode of the current three-part series had been leaked
"If you come across it, please do not share it," the tweet said.
Sherlock producer Sue Vertue also tweeted: "Russian version of #Sherlock TFP has been illegally uploaded. Please don't share it. You've done so well keeping it spoiler free. Nearly there"
The final episode in series four of the popular BBC show, titled The Final Problem, is due to air on Sunday.
On Thursday a special screening of the series finale was shown in London, with those attending the event urged to keep the plot a secret.
A BBC spokeswoman said: "We are aware that content from Sherlock series four, episode three has been illegally uploaded online. We are working to resolve this issue as quickly as possible."
Based on the novels by Sir Arthur Conan Doyle, Sherlock stars Benedict Cumberbatch as the famous detective and Martin Freeman as his sidekick Dr John Watson.