Something terrible has happened to Henry Knight; Sherlock and John investigate the truth about the monstrous creature which apparently killed their client's father. A hound from hell? What seems like fantasy in Baker Street is a very different prospect in the ultra-secret army base that looms over Dartmoor.

Directed by: Paul McGuigan - Mark Gatiss - Steven Moffat - Arthur Conan Doyle

Writer credits: Mark Gatiss - Arthur Conan Doyle - Steven Moffat

Cast: Benedict Cumberbatch - Martin Freeman - Una Stubbs - Rupert Graves - Mark Gatiss

AKA: Sherlock, 4 Years, 6 Months, 2 Days, Шерлок

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