They're united in their passion for Sherlock Holmes but divided by their views on the two (soon to be three) modern takes on the great detective. And this March, the opposing camps will join battle in The Great Sherlock Holmes Debate... 2!
The first event, in November last year, drew live online participants from 23 countries around the world, creating millions of pages of comments on social networking sites.
Since then, the BBC's Sherlock, starring Benedict Cumberbatch, has returned for an even more highly acclaimed second series, while the action-packed Warner Bros movie franchise, directed by Guy Ritchie and starring Robert Downey Jr as Holmes, has proved it has staying power with the hugely successful release of its second instalment, A Game of Shadows.
On 18 March, 25 of the world's top Holmes experts, including actors, directors, historians and writers involved in each of the franchises, will meet in person to once again argue over which is the best Holmes adaptation – and to share their thoughts on Elementary, the controversial modern-day take on Sherlock from US TV network CBS, set to star Jonny Lee Miller and Lucy Liu.
Fans can head over to The Great Sherlock Holmes Debate's Facebook page to see the results of a pre-debate poll, leave comments and find out how to vote for their favourite franchise following the event. The debate will be recorded, with audio and accompanying slides made available to fans afterwards, but there's also a chance to win a place watching it live.
Last year saw a palpable victory for BBC Sherlock in the voting, with popular sites Sherlockology and The Baker Street Babes playing a key part in the win.
The debate, organised by MX Publishing, supports the Save Undershaw campaign, which aims to preserve the former home of Sherlock Holmes creator Sir Arthur Conan Doyle, where he penned many of the stories.
The campaign has a number of celebrity supporters, including Stephen Fry ad Sherlock co-creator Mark Gatiss, who is a patron of the Undershaw Preservation Trust.
Watch a trailer for The Great Sherlock Holmes Debate above and tell us which Sherlock you prefer in our poll below.
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