The producer behind detective show Sherlock has urged fans of the hit U.K. TV series to keep new filming locations under wraps to prevent potential spoilers. Filming for the third series of the popular Sherlock Holmes-based programme, starring Benedict Cumberbatch and Martin Freeman, is currently underway and devotees were recently sent into a frenzy when fan-taken photographs emerged online showing the stars on set in Bristol and Cheltenham, England. Now, as production heads to London, producer Sue Vertue has asked fans to refrain from posting photographs or filming locations on social networking websites, and warned them not to expect much interaction from the show's stars during the "gruelling" shooting schedule. In a message posted on the official Sherlock Tumblr.com blog, Vertue writes, "As many of you are aware, we'll soon be embarking on our first London leg of filming for series 3. I'm also aware that there is quite a lot of speculation about where we're shooting (and) when. I can't stress how much we the producers and Benedict, Martin and the rest of the cast appreciate your love and dedication to our show - we'll endeavour to live up to your expectations for Series 3. "What I am nervous about is that our London shooting schedule is punishing and will really give us very little time to interact with you. The actors really hope you understand that. Also, and I know this is probably asking a lot, the majority of fans and indeed ourselves would REALLY appreciate it if you didn't post pictures or spoilers or ideally our daily locations. Thanks for your understanding."