Which Sherlock episode first aired on BBC One on 8 January 2012?

The Sherlock episode first aired on BBC One on 8 January 2012 is “The Hounds of Baskerville.” It is the second episode of the programme’s second series.

Written by Mark Gatiss and directed by Paul McGuigan, the episode modernises Arthur Conan Doyle’s famous novel The Hound of the Baskervilles. Sherlock and John investigate Henry Knight, who claims that a gigantic hound killed his father on Dartmoor two decades earlier. Their investigation leads to Baskerville, a military research facility, where scientific experimentation and hallucinogenic gas replace much of the original story’s supernatural atmosphere.

The date can cause confusion because “A Scandal in Belgravia” aired one week earlier, on 1 January 2012, and “The Reichenbach Fall” followed on 15 January. “The Hounds of Baskerville” is therefore the correct date-and-title pairing, as well as the second episode of series two.