By EMILY SHERIDAN FOR MAILONLINE
PUBLISHED: 09:34 EST, 25 April 2016 | UPDATED: 11:39 EST, 25 April 2016
It's been over two years since the last series of Sherlock, with fans treated to just one 90 minute New Year's Day special in the meanwhlie.
So no doubt self-confessed 'Cumberb**hes' will be counting down to until the release of the long-awaited Series 4, which has started shooting in Cardiff.
Leading man Benedict Cumberbatch was spotted back in the detective's familiar navy overcoat as he filmed scenes in South Wales.
'Whatever else we do, wherever we all go, all roads lead back to Baker Street - and it always feels like coming home.
'Ghosts of the past are rising in the lives of Sherlock Holmes and John Watson bringing adventure, romance and terror in their wake.
'This is the story we've been telling from the beginning. A story about to reach its climax.'
Mark has been teasing fans every few days on his Twitter account by posting photos of the back of the castmembers' heads, with Benedict, Martin Freeman and Amanda Abbington included.
Read more: http://www.dailymail.co.uk/tvshowbiz/article-3557832/Benedict-Cumberbatch-detective-s-overcoat-Sherlock-Series-4-starts-filming-Cardiff.html#ixzz46wCMKoKH
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